Home > Trip Reports > Saturday February 22, 2014, Chair Peak Avalanche

Saturday February 22, 2014, Chair Peak Avalanche

2/22/14
WA Snoqualmie Pass
158071
140
Posted by shawnskis on 2/25/14 11:12pm
[size=17pt]The Prologue
I€™ve been contemplating whether to post this report for many reasons, one of which is due to the fear of the negative reactions we may get from others in the community. After submitting our report on NWAC there have been comments via their Facebook post that made me reluctant to share more. It seems that with the anonymity many web boards provide today, it is easier to post comments that are judgmental, ultimately discouraging others from sharing. But, it€™s for this specific reason that I€™ve chosen to post our story. My hope is that you read through the events below and think about how we can learn from them. Let€™s begin a healthy conversation which replaces judgment with curiosity. I encourage you to ask questions to better understand why we made the decisions we did, and how we could have done better.


[size=17pt]The Account
our research
This past Saturday, 2 friends and I went up to Alpental with the intention of heading into the back country. I did my homework the night before to ensure I understood the conditions and risks. I reviewed NWAC, TAY, and consulted Topo maps despite the few years of experience I€™ve had in the area. Because of the unusual amount of snow fall, I consulted a friend who is a very experienced BC guide and is respected by the guiding community. He happened to have been out that day with clients and observed extremely stable conditions; skiing on many different aspects, slope angles, ridge lines, and altitudes. With many attempts to test the stability he observed no slides. During the conversation he also mentioned that he had plans to head out to Mt Roosevelt the next day. Based on initial research, our plans were to stay closer to Source Lake and climb towards Pineapple Pass or Chair Peak, but because of my conversation with my guide friend we added Mt Roosevelt as an option to our list of potential goals.

leading up to the slide
On Saturday, we met at the Alpental parking lot and discussed the new option of Mt Roosevelt, ultimately agreeing to make that our primary goal but being open to other options.

As a side note, it€™s important to add that while I have what probably is more education than most with regard to ski mountaineering as well as a handful of years of experience, my friends did not. They are relatively new to BC although well informed and knowledgeable given their level of experience. 

After gearing up, we left the parking lot at 7:45am. The conditions were absolutely amazing with great visibility. We made it to Source Lake in about 45 minutes and decided to continue towards Chair Peak. The goal was to gain access to the Snow Lake area by way of one of the two high saddles.

Throughout our ascent, we continually discussed our options and shared our observations. We saw no evidence of instability. The snow seemed incredibly stable. On the switchbacks up to the saddle there was no sign of slide danger, nor any other slide debris. The snow layers seemed to have great cohesion. We realized NWAC€™s forecast was very different from what we were observing. There was no sign of natural or human triggered slides. While not completely ruling out the persistent slab, we felt comfortable pressing on.

We made good time and topped out in the saddle (47.460662, -121.461107) at about 11:00am. We stopped to refuel and transitioned. We headed down towards Snow Lake with our route to the northwest. The snow was beautiful, light and deep with no signs of any slides. We picked our lines and one at a time made some beautiful turns and met at a designated transition point below. We quickly moved to skin west to a slightly higher plateau and transition (47.462936, -121.463950) for a ride down the couloir to the west side of the lake just below the Chair Peak summit.

the avalanche
NWAC Observation Posting: http://www.nwac.us/observations/pk/101/

As we stopped for our transition, we chose a location on a shelf to the right of the couloir entrance that provided some deflection to a potential slide. It was still exposed, but the best option given what was available. At that point we discussed our options, ultimately agreeing to ski down the couloir. Towards the end of our transition we heard what originally sounded like a jet flying overhead. We looked uphill towards the sound only to witness a title wave of snow accelerating towards us. The sound continued to get louder and we turned to flee. €œThe only thing I remember hearing was Run€¦ Avalanche!,€ my friend recalled.  After 2 or 3 steps we were quickly swept up by the slide. All three of us fought the snow and each of us tried to swim to the top. To my surprise, so many thoughts went through my head in that short amount of time. I tossed my poles, tried to kick off my skis, and wished I had an airbag. As the slide slowed I thought about what I needed to do to save my friends.

We were carried about 50-60ft and were partially buried up to our waists. We quickly located each other, ensuring no one was buried or needed help. After confirming everyone survived without injury, there was a noticeable pause as the realization of what just happened came upon us.

survival mode
After digging ourselves out, we noticed that we stopped at the very edge of the slide path. We felt extremely lucky as most of the slide banked to the left and traveled into the couloir. The slide started at the rock face of Chair Peak and travelled approximately 1900ft down to Snow Lake. We started to look for our gear so we could head back after being rattled by the slide. I fortunately had my skis on and my friends were able to recover their skins and bags as they were on the snow surface, but a Pryor Khyber splitboard and Vokl Nunataq skis were nowhere to be found. We probed for close to an hour trying to locate our gear to no avail. It was critical to locate our gear as without it would make returning back to the car difficult at best. We found nothing and at 1:00pm decided to abandon our search and start the long slog back to the parking lot. We wanted to ensure we returned to the parking lot before nightfall.

We made the decision that going up the slide path was the best exit path, as this was the only firm snow to travel on. All other options put us in waste deep snow which would make it too difficult to efficiently travel. We made our way up the slide path on the firm compacted slab passing several large snow/ice blocks that were the size of refrigerators or bigger. It was apparent that the snow slid on the January layer as we climbed the wall of ice on the approximately 70 degree slope. My friend lead the way cutting steps with an ice axe as we climbed towards the avalanche crown. Visibility dropped to almost zero which slowed our ascent considerably. We continued to talk through our options as we moved. Before reaching the North rock face of Chair Peak, we saw the fracture line and a 10ft crown that traveled to our right about 70-100 ft. (47.460473, -121.465420).

We realized that our exit to the left through the high saddle that gave access to Source Lake below meant that we had to travel approximately 150ft across the fresh snow that had not fractured off. I being the only one in our party who had not lost his skis gingerly skied across the snow field to the ridge and high saddle. (47.459991, -121.463950). One at a time my friends slowly and cautiously followed across the snowfield up to their waists in deep powder. Once we hit the saddle we felt confident we would get back to the parking lot before nightfall. We travelled through the pass and came across our ascent tracks.

Trudging through the deep snow was the ultimate tease, we ran across multiple parties heading up and conveyed the events of the day. Three and a half hours later we hit the parking lot and collapsed into our vehicles. Definitely a day to remember and although we lost gear, we were all thankful to be alive and uninjured.

https://dl.dropboxusercontent.com/u/54912395/Chair%20Peak.jpg[/img]
Map of Route €“ maps.google.com


[size=17pt]The Epilogue
As mentioned above, I decided to post this story for the purposes of education. With the beers that followed our experience, we met up with my guide friend to discuss the day€™s events and our decision making. And, as expected the conversation still continues today. From those conversations came some interesting observations that I believe would be valuable to add to this discussion.

nwac forecasts
Firstly, I learned that very well respected guides, were skiing with their clients on similar terrain last Saturday. All of them assessed the same conditions and made similar decisions that we did.

This leads me to discuss the information available on NWAC. The information provided by NWAC didn€™t seem consistent with what we observed that day. NWAC forecasted human triggered slides as 'considerable€™ while from our account, they were extremely difficult to initiate. Also, naturally occurring slides weren€™t mentioned in the NWAC forecast although we know that there was at least one. I do not point the finger at the individuals who have an extremely difficult job of forecasting the conditions and assessing the risk. But, I think it€™s interesting that many well respected and experienced professionals are making decisions that contradict the NWAC forecasts. Is it possible that NWAC is generalizing their forecast because they need to cover such a large area? Conditions can vary within a few miles of each other.

To be fair, I do not have deep knowledge of NWAC€™s process but it€™s my understanding that they have roughly 5 professionals in the field, assessing conditions across the North West. From my laymen€™s perspective, that seems insufficient. What changes can NWAC make and how can we participate to improve their forecasting accuracy? Would it be beneficial for more professionals in the BC to report conditions to NWAC and/or the public on a daily basis? There doesn€™t seem to be a community that encourages experts to share knowledge more broadly. For example, my understanding is that the Alpental ski patrol are on the mountain daily, assessing avi danger. But, they do not communicate their assessments publically. Should they?

a community of learning
Lastly, in general, there doesn€™t seem to be a community that allows for healthy conversation and debate for the purposes of education and safety. There is, what I hope, a small number of individuals that discourage reports such as this one with judgmental comments that don€™t add to the conversation. I was encouraged to see a healthy discussion about the Chair Peak slide on TAY over the past few days (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30876.0). Although the conversation is mostly positive and educational, it also serves as an example of how there€™s a small group of individuals who are not there to learn and understand.

At the risk of belaboring my point, I thought I would add another interesting observation. Another post on TAY described 3 people who skied the Slot on the same day of the Chair Peak avalanche (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30882.0). In my opinion, the Slot is arguably as risky as traveling out to the North side of Chair Peak. Interestingly, our experience produced countless comments on TAY while the Slot post received two, neither of them judgmental. Why do posts that highlight a positive outcome get no scrutiny even though the risks were just as high? I€™ve read comments on TAY that congratulate individuals who have taken the same risks we did but ended up with a positive outcome.

Ultimately, I would like to see our passionate community show a thirst for knowledge and understanding along with compassion. Only this way will we all be fortunate to do what we love and come home to our friends and families each night.

conclusion
In summary, I believe we followed our education and did many things right. We conducted our research and continued to communicate as we moved through the terrain. We observed that the conditions contradicted the NWAC forecast to some extent and believed moving forward was an acceptable risk for our party. Skiing in the BC is inherently risky. We do our best to stay safe, accepting a level of risk that is specific to each individual and group.




I wanted to thank my guide friend and 2 skiing friends who helped think through our story and co-wrote this report. I also wanted to give special acknowledgement to my 2 skiing friends who shared this life altering experience with me. Thanks for your support and saving my life.

Awesome writeup. Thank you!  Glad you decided to ski a little before dropping into the couloir down to Snow Lake!

Agree, excellent write up, I think TAY is a great forum to share as it very much hits your target audience. Regarding ski patrol, Crystal Mt. will occassionally share some avy information on their blog, http://www.blogcrystal.com/ but not in a structured or regular basis.  The danger of ski patrols posting observations is that in-bounds conditions can vary significantly than backcountry, so any inclination that those observations apply equally to backcountry could be bad.  Sidecountry observations would certainly be more relevant.

As for slot, and really any report on steeper terrain, I am pretty much thinking the same thing. The deep layer is there in many spots, and catestrophic.  Lastly, can't comment on the specific report from NWAC but in general they have been calling out the deep layer threat.

As for sharing, TAY has been the most relevant forum I have found, as folks will share their snowpack observations and locations, and occassionally throw in vid or pic of snowpack analysis, but you can be sure there are many more being done than posted.

Thank you for sharing your story.  I am very happy that this had a happy outcome.  It certainly makes me reflect on my own evaluations/decision making/terrain selection.

It's buried in the text but in my TR from the previous day,
http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30859.0 (Feb 21),
I mention running into an NWAC pro who warned us of the deep layer on big slopes. Dunno how or if that got communicated through the system though, and I got a feeling it was a "lower probability but high consequence" kind of threat.

This is perhaps the best avi writeup I've seen to date. The lessons I take away from your story is that your prudent decision to transition on a ridge feature saved your lives, and that there will be some sweet gear at the bottom of Snow Lake this summer.


I'm curious....you state many examples of why you guys decided that it was OK to be where you were that day.  In hindsight, was there any information you had that would have made your decision a no-go for that day? 

Thanks for stepping up when you know there will be some criticism. I don't have any criticism for what you guys did. I can only say the reasons that I chose different terrain that day and similar ones. After a few years of this sport many of us have begun to focus on what we don't know about the risks and to find ways to mitigate it more rather than to find the true barriers of what is safe or not. One rule of thumb I have fallen back to is to ski lower angled older treed terrain following a storm like this until I have more assurance that a layer like that is stable. That assurance wasn't there for me with this storm because the only dramatic change throughout the storm cycle was that more and more new snow continued to pile on top. The nwac rating, people's pits, trip reports etc. we're irrelevant too me until I saw some sort of warming or soaking event that would thoroughly test the bond on that layer. I likely would have kept to less open slopes until such an event occurred and even afterward I would have had some concern about that layer until after the first large warmup in the spring. I am not an expert and unfortunately I have not always been smart enuf to take my own advice but for what it is worth that is why I chose to stay away from terrain like chair and even the slot. I would not have posted on a trip report about chair or the slot on days with similar risks simply because I am not an expert and couldn't tell those people whether or not they made a decision that was unsafe. It is that that inability to know whether it is unsafe however that kept me in more protected terrain. Thanks again for sharing and I am glad you all came out ok. You are in good company with people who have made mistakes.

It's the Internet.  People will be caustic.  

The NWAC has to paint with a broad brush.  And frequently theory as much as observation seems to drive their forecasts.   Agreed that stability in the upper snowpack was great.   I think there forecast was influenced by the fact that that much snow simply renders normal paradigms  about snowpack insufficient.

Everyone was or should have been aware of the potential for these catastrophic slides.  Most people probably realized (as did NWAC) that a skier triggered slide on the crust was highly improbable. Yes post storm slides of this scale were documented in a few spots across a huge amount of terrain  but I'd say you got extremely unlucky!   Many, many other BC skiers put themselves in similar positions whether they realized it or not.

Your incident reminds me of the 1999 Valentines Avi at Baker.  Yes there had been a ton of snow but no one could have predicted that.   So is the layer still suspect?  Will more enormous slides occur?  No one knows and no one is going to be able to credibly assess the threat.   Here on out (as always) everyone's going to have to make their own decision on whether they can operate with a certain unassessible level of risk.

Thanks so much for posting up (both here and at NWAC). We all understand your reluctance, but your excellent, detailed write up is of great value. Don't worry about the negative comments -- it's very easy to say 'It would never happen to me' from the internet. I don't know about other folks, but in our costal climate my investigation of snow stability is usually directed at the top couple feet (which I think is a good practice that I intend to continue). Your experience shows that deep instabilities can play a role in real-life skiing situations.

I'm very glad your party was not hurt or killed by this large slide.

Excellent report.  Thank you for taking the time to post this so that we can all learn from your experience. 
As per your comments:  "There is, what I hope, a small number of individuals that discourage reports such as this one with judgmental comments that don’t add to the conversation. I was encouraged to see a healthy discussion about the Chair Peak slide on TAY over the past few days (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30876.0). Although the conversation is mostly positive and educational, it also serves as an example of how there’s a small group of individuals who are not there to learn and understand."

* Hopefully it is the waning days of the "WTF" crowd as we move to a more sophisticated and  constructive discussion about avalanche incidents. 

Thank you for sharing. Sounds absolutely terrifying. You and your friends are blessed to survive a brush with an avalanche of this nature.

Unless we're in the care of a mountain guide, its important to remember that when we're in the mountains we are 100% responsible for our own actions, and the outcomes of those actions. A mountain guide's green light and NWACs warnings were all pertinent pieces of information to assemble your plan for the day, but in the end it was your choice that put you in harm's way.

I find the mixed signals you discuss to be very interesting (NWAC's report vs. guide's report). I myself have made bad decisions due to just such mixed signals. When the discussion gets focused on one particular subject (in this case the storm snow instability) it can cause us to forget to consider other, equally important, dangers (the deep slab). 




author=RonL link=topic=30926.msg129511#msg129511 date=1393432472]
Thanks for stepping up when you know there will be some criticism. I don't have any criticism for what you guys did. I can only say the reasons that I chose different terrain that day and similar ones. After a few years of this sport many of us have begun to focus on what we don't know about the risks and to find ways to mitigate it more rather than to find the true barriers of what is safe or not. One rule of thumb I have fallen back to is to ski lower angled older treed terrain following a storm like this until I have more assurance that a layer like that is stable. That assurance wasn't there for me with this storm because the only dramatic change throughout the storm cycle was that more and more new snow continued to pile on top. The nwac rating, people's pits, trip reports etc. we're irrelevant too me until I saw some sort of warming or soaking event that would thoroughly test the bond on that layer. I likely would have kept to less open slopes until such an event occurred and even afterward I would have had some concern about that layer until after the first large warmup in the spring. I am not an expert and unfortunately I have not always been smart enuf to take my own advice but for what it is worth that is why I chose to stay away from terrain like chair and even the slot. I would not have posted on a trip report about chair or the slot on days with similar risks simply because I am not an expert and couldn't tell those people whether or not they made a decision that was unsafe. It is that that inability to know whether it is unsafe however that kept me in more protected terrain. Thanks again for sharing and I am glad you all came out ok. You are in good company with people who have made mistakes.


I really like and agree with what Ron said. I'm also glad you decided to talk about your experiences. Like Ron, I was actually surprised to hear about people skiing "the Slot" recently. I didn't say anything because I haven't skied it myself and am no expert either. I decided that perhaps because of it's steepness it runs fairly regularly, so was maybe OK to ski.

I've got a couple of points to make. First of all, although I don't consider myself an avalanche/snowpack expert, I feel very qualified to assess dangerous locations in a variety of conditions. I know what objective dangers are, and how to try to avoid being caught by one. A lifetime of rock climbing overhanging, vertical, and low angle rock has taught me (sometimes the hard way) where the danger zones are. Guess what? Anywhere under a steep tall mountain is one of them! I used to climb the "day climbs" at the bottom of El Capitan. One day I had 2 or 3 pitons dropped towards me from a few thousand feet up. The buzz sound of that angle coming down at terminal velocity is still in my mind. I decided right then that it was only worth being at the base of a wall if you were there to climb it - not just hike or practice. A few years later this was reinforced when I had stupidly taken my family to a great viewpoint I knew in Yosemite. Again, this was under a cliff of great proportion, and some stonefall came down and nearly took us out. Snow and ice fall far more often than rock, so for me it seems very obvious that one of the worst possible places to ski during a period of high danger would be directly below a large, steep, mountain. Your report shows you knew this could be a problem by your life saving decision to move out of the way a bit more. But you still don't seem to realize that you were in the wrong place to began with. Perhaps your guide is the best guy in the world - but if he was taking me under a face like that in a period like this, I'd turn around every time!

The other point I have to make is that there are lots of great reasons to be up in the mountains skiing. When making daily objectives we need to remember that skiing doesn't have to be steep to be fun. The lines don't need to be long and continuous. The powder doesn't need to be the lightest, or the sun the best angle. Those days will happen when the conditions are right - and if we are still there to enjoy them.

Brian

Well said, Brian.

Thanks for sharing.

A couple thoughts. I went up in that area the day before and noted good cohesion, but I was also aware of rapid loading and wind. We chose to stay in the trees, and I would say my level of risk acceptance is higher than most. I've definitely put myself in bad situations, and probably will again, it's kinda the nature of the beast.

In your write up it seems that you take no blame, and still think you did everything right. Agreed while the upper snowpack seemed stable, just putting yourself in that area was a bad call IMO. I wasn't on the armchair quarterback committee, and wanted to hear your story before commenting.

Also if you read the forecast discussion and not just looked at the danger rose, while it was a considerable rating, it warned of a possible deep slab, and the possibility of a natural trigger such as a cornice fall that could create a large destructive avalanche that could propagate to old crust layers.

What happened to you is exactly what the NWAC forecasted, so to blame them for a bad forecast is a cop out IMO, just the day before some friend and I were on a tour and commenting on how their forecasting seemed conservative this year.

Plus the definition of considerable "Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential."  The majority of avalanche fatalities are on considerable days.

I'm glad you made it out OK and appreciate the write up, and it seems you were in the wrong place at the wrong time, but that could have been avoided

When I saw the report from the Slot, 2 things crossed my mind:

1) Those lucky *****s! I bet the skiing was awesome.
2) That was not the kind of terrain I chose to be in on Saturday.

The Slot, more than any other serious tours I know, tends to get hit early after the storm. I think people are "getting away with it" more often that they might know. However, when we hear about the tours like this that go well, I think most of our reactions are first in category (1) because we know that everything went okay, and we wish we had gotten after it, too. People aren't going to be critical (especially on a forum like this) when things go well, because they don't want a reputation as a nay-sayer weenie-pants. I think the _lack_ of responses to the Slot post probably is due in part to the conflicting feelings people have between congratulating the party and wanting to warn them about the dice game their decision was.

Thank you for the honest write up, we're all glad this one didn't turn out with injuries or worse.

Also a  couple of points -

NWAC forecasts are general forecasts and cannot target micro terrain and aspect that experience large fluctuations in wind, snow fall, and transport. They are very helpful for general awareness and are a great resource to include in trip planning, but still rely on field observation and communication from ski area patrols, which I guarantee goes on between NWAC and Alpental patrol, several of which are members on this site.

About differences between the Slot and that slope on Chair peak and the differential treatment- well a report of a natural D3 avalanche with a 10 ft fracture is always going to draw more attention.  However even when trying to compare one "risk" with another "risk" they are not equal, again due to differences in loading and in shedding. The Slot is more prone to frequently clean itself out and so is less likely to be affected by a persistent deep layer, but because it does clean out more regularly it also increases the chance of going for a ride. Accessing it on those S. facing slopes of Snoqualmie has it's own set of issues entirely different from dropping off the back.   That face of Chair above snow lake doesn't slide as often, but that gives it the potential to go big when it does.  This is not to say you made a poor choice and those that chose to ski the Slot made a good choice, just that the choices are not equivalent when considering surface vs deep slab avalanches.

Your transition zone off the back is a little odd. One usually doesn't have to skin and de-skin coming off the saddle down to Snow lake, I have only done that when lapping the rollers down to that last bench.  However, it may have kept you out of the deposition zone.  Again, glad it turned out mostly ok.  

I’ve been down that couloir a few times, never in epic conditions mind you and only a couple of times in actual decent powder but nothing like what had fallen leading up to your trip.  I can’t make the judgment whether I would have gone or not since I’ve been laid up so far this season.  The usual route starts from your exit col as I’m sure you are aware and gives the option of skirting the traverse and then dropping the couloir for a “cleaner fall line” or dropping to where you ended up transitioning and entering there neither of which require an extra transition.  I have seen big fractures along the traverse although these were likely caused by big cornice drops given the truck size chunks of ice we observed.  However, every time I’ve been through it there has been evidence of a slide.  It’s a tough one to call since you rightly said that the new snow was stable and whoever routinely digs down 10+ ft doing a pit to test that weak layer?  It that weak layer wasn’t there (which by the sounds of it we all knew it was) then even with that large snowfall it probably would have skied just fine judging by your observations and nobody could fault you on that one.  My takeaway, if there is high probability of a weak layer down deep and it’s an avalanche prone slope then wait for it to slide or settle and get new snow before trying it again.  Whether I can stick to that mantra is another thing of course.

Thanks for the write up, hits home given its one of my local spots.

author=RonL link=topic=30926.msg129511#msg129511 date=1393432472]
Thanks for stepping up when you know there will be some criticism. I don't have any criticism for what you guys did. I can only say the reasons that I chose different terrain that day and similar ones. After a few years of this sport many of us have begun to focus on what we don't know about the risks and to find ways to mitigate it more rather than to find the true barriers of what is safe or not. One rule of thumb I have fallen back to is to ski lower angled older treed terrain following a storm like this until I have more assurance that a layer like that is stable. That assurance wasn't there for me with this storm because the only dramatic change throughout the storm cycle was that more and more new snow continued to pile on top. The nwac rating, people's pits, trip reports etc. we're irrelevant too me until I saw some sort of warming or soaking event that would thoroughly test the bond on that layer. I likely would have kept to less open slopes until such an event occurred and even afterward I would have had some concern about that layer until after the first large warmup in the spring. I am not an expert and unfortunately I have not always been smart enuf to take my own advice but for what it is worth that is why I chose to stay away from terrain like chair and even the slot. I would not have posted on a trip report about chair or the slot on days with similar risks simply because I am not an expert and couldn't tell those people whether or not they made a decision that was unsafe. It is that that inability to know whether it is unsafe however that kept me in more protected terrain. Thanks again for sharing and I am glad you all came out ok. You are in good company with people who have made mistakes.



I agree with Ron too. I used to backcountry ski over 100 days/year and would get caught in a couple slides/season. One was scary. All on "low" avalanche days. Friends have died in avys. And after a few years like that I did a calculation. What I'm doing might be 99% safe, but I'm doing it over a hundred times. The numbers will get me if I don't change. So I changed to a rule of only going into real avalanche terrain when the danger rating was low for at least 3 days in a row. Obviously, just waiting for spring is the best. But humans do not have good perceptions of risk and numbers. 99% feels pretty damn safe. But a 1% risk of a catastrophic event is actually an insane risk. I had a strong feeling I would not live another 5 years at the rate I was going.

There are plenty of ways to theorize about things. To justify conditions and choices. But neither guides, NWAC, nor ourselves doing assessments on the mountains, are very good when comes to calculations of odds like that. It's a numbers game. Numbers and emotions don't mix well, so it's hard to follow the numbers instead.

Thanks for the great post. For this great discussion. Glad you're all OK.

I looked at the archive forecasts for Friday and Saturday for both Snoqualimie Pass and SP near and west of the crest and near and east of the crest and found nothing inconsistent with the forecasts and what happened to the OP's party. The forecasts basically described what happened as a possibility/probability. I agree with whoever posted that blaming NWAC for this is a cop out.

It wound be curious to know where the "guide friend" was skiing on that day on the same aspect and if he exposed himself and his clients to the same objective hazards and consequences.

The recent reports of people "getting after it" given the weather history and forecasts is a bit puzzling to me, but I have a much lower risk tolerance than I used to.

It took a lot of courage to post this write up, maybe edit it to be a bit more objective about your decision making after some more reflection.

Thanks for stepping up and providing this write-up, knowing that there would be people who would criticize, some productively, others not. It was a very helpful write-up, especially that map, which is awesome; probably the best one I've seen included with an incident report.

A few general comments, many of them repeating what others have said:

*First and foremost, I am really glad you guys made it out unharmed with nothing more than a scary experience and incredible story. We are all certainly glad to be discussing a close call rather than a horrendous accident which claimed lives. Losing people who are in our communities and share similar interests is tough, even if we don't know them personally.

*What you experienced actually fit well with what NWAC was forecasting, rather than contradicted it, at least as I remember the forecast. They mentioned the lowering probability that humans would trigger slides, but still the very real (though smaller) risk that slides of mammoth proportions would occur naturally. They have featured this warning nearly daily for weeks, and included quite a few videos showing evidence of natural and explosive triggered slides that ran huge, but would likely not be triggered by a human. These may be the most truly misleading type of conditions to judge, since any stability tests we can do will show promising results, but the unknown chance of 'the big one' is difficult to see or understand.

*With conditions like that I think it really comes down to deciding how much risk we want to accept as individuals, and then rolling the dice. This is why a lot of people, despite wonderful snow conditions and seemingly quite stable snow, chose to ski rather mellow slopes, tree covered terrain, etc. Chances are most people could have gone on steeper slopes and been totally fine given the lack of self-triggering slides, but chose not to. Again, it just comes down to the decision of personal acceptance of risk, which is hard to criticize somebody on in either direction

*Guide is pronounced "guide", not "god." Sorry if I get flack from people who guide (which includes friends of mine) about this, but I just have to say it. Because somebody guides for a living doesn't necessarily make their knowledge, logic or decision making inherently better. How many guided trips end up with avalanche fatalities? Plenty. The Wallowas accident earlier this season was a guided trip. Remember the 7-fatality incident in BC from 2003? Guided, and led by a very experienced guide at that. The list goes on. I have read several times that statistically, the more avalanche training education one has, the more likely they are to fall victim to a slide. There are plenty of people who participate on this site that have more practical experience than many guides. Who's advice would you trust more, a 24 year old guide who has, let's say, 7 years of experience in the mountains, or a 60 year old lawyer, engineer or whatever who has traveled in the mountains for 40+ years and is still alive to share that experience? It could be either, given the circumstances or the individuals. We could just as easily be reading about this incident having happened to one of the mentioned guided groups, instead of yours. I think it would be wise to not factor in a guide's comments to increasing your level of risk acceptance, be it conscious or not.


And one final comment on something you said:

In my opinion, the Slot is arguably as risky as traveling out to the North side of Chair Peak. Interestingly, our experience produced countless comments on TAY while the Slot post received two, neither of them judgmental. Why do posts that highlight a positive outcome get no scrutiny even though the risks were just as high? I’ve read comments on TAY that congratulate individuals who have taken the same risks we did but ended up with a positive outcome.

You hit the nail on the head here. This was discussed pretty extensively on another thread about the culture of risk and "going big." The responses people give to these more-risky endeavors tend to reinforce the behavior and lead to more of it. Occasionally you'll hear criticism but more often you'll hear "way to go", "sick, bro!", "badass!", "you guys rock", or something along those lines.

In the interest of giving fair treatment to a report with a positive outcome, I'll restate what I said in the other thread about your incident: I think skiing the slot that day was stupid. I wouldn't have done it, neither would most of the people I ski with. However, some people are willing to bite off more risk, and I certainly understand that. That party likely saw the same results displaying relatively stable snow, but they also ran the risk of the exact same thing that you experienced.

Though as you note, the positive outcome didn't result in the same condemnation and armchair QBing. It would probably be fair if people gave the same treatment of criticism (hopefully constructive!) of positive outcome endeavors, but I doubt we will see that, since it will widely be painted as jealousy, or being a wet blanket.


Thanks for sharing this writeup. I'm glad you guys got through it intact, and that you managed the snow slog out before being benighted.

Some of my thoughts mirror those of kamtron, Aaron, and RonL, fwiw.

Two winters ago, I was fortunate enough to glom on to a guided hut trip in BC that was guided by Ken Bibby, a very experienced guide who also teaches for the CAA. I suckered him into giving our group a version of a lecture he'd done for one of their workshops. He walked through his mountaineering history from before guiding through early days guiding to the current era. He focused on the impact of ego on decision-making. He also had a nice powerpoint presentation to go along - his early era self-image was of a gnarly mountaineer, illustrated by a photo of himself doing a "cliffhanger" type move of jumping a crevasse with two ice tools in hand. Gnarly. Then he moved to his first experiences guiding, including being tail guide on a heli trip where he had reservations about the conditions but he was the new guy and he followed along and they lost a client that day. His self image photo for this phase was of a clueless dufus. He kept working though, and built his experience and instincts, and told a story of a trip in a big fat spring snowpack where he decided to be extra cautious about checking a bridged 'schrund with a probe, one that is apparently regularly crossed via the bridge in spring, but he had a funny feeling and wanted to be careful. As he was probing, the very thick bridge dropped away in front of him into the abyss. He sheepishly returned to his waiting clients above and calmly led them the long way around. He then showed his current self-image photo - him with his wife and kids. And he talked about the importance of humility and maintaining a healthy margin of error that is in proportion to the potential risks at hand. He noted that all his experience and training told him that skiing across that bridge was fine on that day, but it turns out it wasn't true.

I'd contrast Ken's conclusions with this quote from the NYT article about the Tunnel Creek incident:
“It’s a cultural shift, where more skiers are going farther, faster, bigger,” said John Stifter, the editor of Powder magazine, who was a part of the group at Tunnel Creek in February. “Which is tending to push your pro skiers or other experienced, elite-level backcountry skiers that much farther, faster and bigger, to the point where there’s no margin for error.”


My impression is that committing to terrain that empties a broader slope leading to a loaded ridge crest into a relatively narrow and long couloir that piles its poops onto a flat below when we have such a deep load of snow over the last bomber crust is putting a LOT of faith in one's ability to assess the probability of a slide. I too wonder if those experienced guides were leading clients into truly similar spots; if so, I hope I'd join RonL in balking. As it was, on Saturday we were very careful in picking our way down meadow-skipping style terrain that was in the 20+ degree range for the most part, and which was very broken up by benches, despite seeing no classic signs of instability. The depth and apparent complex layering just spooked us and we felt that our usual heuristics were likely to fail us. We wanted a healthy margin of error. I'd add that on the ridge crest we reached, I noticed a fair bit of snow on the move in the wind. Another party which explored a bit further along the ridge noticed larger-than-usual cornices. I don't know where the snow would have been depositing along the ridge crest above you, but in any case could the fact of blowing snow have significantly changed the picture, up well above your transition point, from what your guide friends saw the day before?

author=Jim Oker link=topic=30926.msg129539#msg129539 date=1393444212]
Thanks for sharing this writeup. I'm glad you guys got through it intact, and that you managed the snow slog out before being benighted.

Some of my thoughts mirror those of kamtron, Aaron, and RonL, fwiw.

Two winters ago, I was fortunate enough to glom on to a guided hut trip in BC that was guided by Ken Bibby, a very experienced guide who also teaches for the CAA. I suckered him into giving our group a version of a lecture he'd done for one of their workshops. He walked through his mountaineering history from before guiding through early days guiding to the current era. He focused on the impact of ego on decision-making. He also had a nice powerpoint presentation to go along - his early era self-image was of a gnarly mountaineer, illustrated by a photo of himself doing a "cliffhanger" type move of jumping a crevasse with two ice tools in hand. Gnarly. Then he moved to his first experiences guiding, including being tail guide on a heli trip where he had reservations about the conditions but he was the new guy and he followed along and they lost a client that day. His self image photo for this phase was of a clueless dufus. He kept working though, and built his experience and instincts, and told a story of a trip in a big fat spring snowpack where he decided to be extra cautious about checking a bridged 'schrund with a probe, one that is apparently regularly crossed via the bridge in spring, but he had a funny feeling and wanted to be careful. As he was probing, the very thick bridge dropped away in front of him into the abyss. He sheepishly returned to his waiting clients above and calmly led them the long way around. He then showed his current self-image photo - him with his wife and kids. And he talked about the importance of humility and maintaining a healthy margin of error that is in proportion to the potential risks at hand. He noted that all his experience and training told him that skiing across that bridge was fine on that day, but it turns out it wasn't true.

I'd contrast Ken's conclusions with this quote from the NYT article about the Tunnel Creek incident:
My impression is that committing to terrain that empties a broader slope leading to a loaded ridge crest into a relatively narrow and long couloir that piles its poops onto a flat below when we have such a deep load of snow over the last bomber crust is putting a LOT of faith in one's ability to assess the probability of a slide. I too wonder if those experienced guides were leading clients into truly similar spots; if so, I hope I'd join RonL in balking. As it was, on Saturday we were very careful in picking our way down meadow-skipping style terrain that was in the 20+ degree range for the most part, and which was very broken up by benches, despite seeing no classic signs of instability. The depth and apparent complex layering just spooked us and we felt that our usual heuristics were likely to fail us. We wanted a healthy margin of error. I'd add that on the ridge crest we reached, I noticed a fair bit of snow on the move in the wind. Another party which explored a bit further along the ridge noticed larger-than-usual cornices. I don't know where the snow would have been depositing along the ridge crest above you, but in any case could the fact of blowing snow have significantly changed the picture, up well above your transition point, from what your guide friends saw the day before?


Great description of how one deals with risk throughout the course of their life Jim.
As others said earlier, people have varying levels of risk tolerance. But if one is leading a group of less experienced people, one must lower their tolerance to at least the lowest common denominator.
In group situations, I don't think this happens too often, and the quiet and risk averse people that don't know enough to speak up or are shy to, get led into dangerous positions. I've played "guide" in these group situations and it's always hard to lower risk tolerance in the moment. But it's wrong not to.

thanks for the write up.  stoked on the good fortune your group saw that day.

re the slot report from that day....as soon as i saw that report and heard about the chair slide i was going to post a reply in each to link the two. mostly as a holy shiz you (slot poster) just got lucky.  realized that i've also been lucky so i held off on posting that link.

nice to hear how many folks backed off as these storms rolled through.  here's to this week's weather helping rid us of that nasty bond deep down.

Thanks for posting this. I've been finding that my usual rules of thumb for avalanche safety in the PNW need to get re-evaluated in winters like this. Your report further hi-lights that point. I've become very used to skiing and managing storm snow risk, but get little to no practice with deep instabilities

If you aren't already aware, Second Ascent is hosting a series of talks by NWAC forecasters and one happens to be tonight. https://www.facebook.com/events/586714731411293/?previousaction=join&source=1

Just some observations of my own. Rather than tell you what you did wrong, or judge, or criticize, I'm going to share with you the elements of your trip that are common to trips where avalanche involvement resulted in a fatality. Except for the fact that no one was killed, your accident report is a carbon copy of several accident reports I was asked to review over the past three months. All these reports follow the same general template, and they all contain the same information. To this point:

* "We're experienced, we're educated"
* "We met somewhere and discussed the avalanche report."
* "Our friends are guides" or "we saw guides".
* "Throughout our ascent, we continually discussed our options and shared our observations."
* "We saw no evidence of instability."
* "The snow seemed incredibly stable."
* "While not completely ruling out the persistent slab, we felt comfortable pressing on."
* "Other people were doing it too."
* "The snow was beautiful, light and deep with no signs of any slides."
* "We were surprised by the avalanche."
* "We extracted ourselves from the scene safely."

These reports are usually incredibly revealing, in terms of what is said and also what is not said. Usually the main part of the text is focused on all highlighting one's actions in a way that will reinforce the reader's perception that the touring party is/was smart and experienced, and that what happened was either unexpected, or was an unusual edge case that arose from the confluence of seemingly unrelated or unforeseeable factors.

I want to be clear: I'm not saying that you are an amateur, or that you were overly concerned about how this would read. I'm saying that your accident report very closely matches accident reports written by backcountry ski parties that demonstrate low skill despite self-assessing their education, experience, and skill as better than average ( or even high ) across the board. Very often, backcountry parties with low skill who are involved in an avalanche accident want to make sure that everyone knows they got the details exactly right, but they fail to see how they got the fundamentals absolutely wrong.

It's very tough to use one's hard-gained skills to turn a sow's ear into a silk purse.

Thanks for the report - food for thought.

IMO - this is the take-away:

*With conditions like that I think it really comes down to deciding how much risk we want to accept as individuals, and then rolling the dice. This is why a lot of people, despite wonderful snow conditions and seemingly quite stable snow, chose to ski rather mellow slopes, tree covered terrain, etc. Chances are most people could have gone on steeper slopes and been totally fine given the lack of self-triggering slides, but chose not to. Again, it just comes down to the decision of personal acceptance of risk, which is hard to criticize somebody on in either direction


---You only have to be wrong once; how important is that powder run, really?

Again, it just comes down to the decision of personal acceptance of risk, which is hard to criticize somebody on in either direction


In many ways I agree and have pushed the risk zone myself, BUT others beyond the crew taking the risks get involved when things go south.  Nearby parties are often the first-responders and S&R teams get activated when snow gets mean and usually feel a strong obligation to help in frequently hazardous consitions.  In increasingly busy BC ski areas, other parties taking lower risk options can be exposed to the decisions made by less risk adverse parties. 

Having lost plenty of friends to the mountains, their acceptance of risk has impacted me and other friends and families.  A well considered risk pulled off is an amazing accomplishment, but a steady diet of increasingly riskier adventures fueled by failing to prove the negative makes the line between experience and bravado seem mighty thin and porous.

It hurts every time I read of severe injury or death where accustomed behavior directed the risk assessment and route choice.  Call it quarterbacking or "WTF" but I always appreciated being told bluntly by my peers or mentors that I had screwed up.   

author=CookieMonster link=topic=30926.msg129566#msg129566 date=1393456291]
Just some observations of my own. Rather than tell you what you did wrong, or judge, or criticize, I'm going to share with you the elements of your trip that are common to trips where avalanche involvement resulted in a fatality. Except for the fact that no one was killed, your accident report is a carbon copy of several accident reports I was asked to review over the past three months. All these reports follow the same general template, and they all contain the same information. To this point:

* "We're experienced, we're educated"
* "We met somewhere and discussed the avalanche report."
* "Our friends are guides" or "we saw guides".
* "Throughout our ascent, we continually discussed our options and shared our observations."
* "We saw no evidence of instability."
* "The snow seemed incredibly stable."
* "While not completely ruling out the persistent slab, we felt comfortable pressing on."
* "Other people were doing it too."
* "The snow was beautiful, light and deep with no signs of any slides."
* "We were surprised by the avalanche."
* "We extracted ourselves from the scene safely."

These reports are usually incredibly revealing, in terms of what is said and also what is not said. Usually the main part of the text is focused on all highlighting one's actions in a way that will reinforce the reader's perception that the touring party is/was smart and experienced, and that what happened was either unexpected, or was an unusual edge case that arose from the confluence of seemingly unrelated or unforeseeable factors.

I want to be clear: I'm not saying that you are an amateur, or that you were overly concerned about how this would read. I'm saying that your accident report very closely matches accident reports written by backcountry ski parties that demonstrate low skill despite self-assessing their education, experience, and skill as better than average ( or even high ) across the board. Very often, backcountry parties with low skill who are involved in an avalanche accident want to make sure that everyone knows they got the details exactly right, but they fail to see how they got the fundamentals absolutely wrong.

It's very tough to use one's hard-gained skills to turn a sow's ear into a silk purse.


I for one thinks this about sums it up.

Well spoken Cookie Monster. For the few that think this is too harsh... Perhaps you haven't yet seen or experienced firsthand the harsh reality of being in the wrong place at the wrong time. Or perhaps you don't have children that could have been followers on such an outing. When I see a report like this, it's not long before I start thinking about how I'd be feeling if my son or daughter was one of the followers that almost - and could have easily died. That would be harsh!

author=CookieMonster link=topic=30926.msg129566#msg129566 date=1393456291]
* "We're experienced, we're educated"
* "We met somewhere and discussed the avalanche report."
* "Our friends are guides" or "we saw guides".
* "Throughout our ascent, we continually discussed our options and shared our observations."
* "We saw no evidence of instability."
* "The snow seemed incredibly stable."
* "While not completely ruling out the persistent slab, we felt comfortable pressing on."
* "Other people were doing it too."
* "The snow was beautiful, light and deep with no signs of any slides."
* "We were surprised by the avalanche."
* "We extracted ourselves from the scene safely."


All of these things (except perhaps the last two) are also mentioned in a large number of trip reports where there is no avalanche or injury.  I'm not sure how I would use those to differentiate a non-threatening situation from a threatening one.  To be a useful predictor of hazard or non-hazard a particular attribute has to be unique to a particular type of situation.  Maybe you didn't intend them to help discriminate between safe and unsafe.

I guess I'm a bit more charitable in my interpretation of the report.  Or perhaps I can't see how my decisions would have been much different.  The group did pre-trip research and was making an effort to manage the hazardous terrain by picking what they thought was a safe spot to transition.  It sounds like they were caught on the very edge of a pretty massive slide path.  Had the crown ripped at only 8 feet instead of 10 would they have safely watched the slide go by?  In that case would we be praising their terrain management?  Who knows?

What I am certain of is that there is no black and white in terms of assessing risk.  Why do most of us choose to cross open slopes one by one?  Because we know there is always risk (even when avy risk is moderate or below).  Over the years I've read NWAC and TAY reports of avalanches ripping through treed areas and all kinds of other places I'd never have expected.  Risk is inherent in our sport.  Of course, we all choose to manage it in our own way.

As I read the report from Chair Peak I can't help but wonder if there but for the grace of god go I.  I'm not sure how long it will take for the deep instability to become "safe".  I do know that with each passing day it becomes "safe" for more people while for others it remains "unsafe".

I think the best one can do is take an avy course, digest all the pre-trip intel available, manage hazard conservatively in the field, and, uncomfortable as it may be, hope for a little good luck on the mountain.

Be safe out there.

Thanks for sharing this.  It has already added to the community at TAY.  

I have been troubled by the large amount of recent snowfall, in terms of how would I go about assessing the avalanche risk.  Would I need to dig a 10 foot deep pit to check the January layer?  I don't think I'll be doing that, so does that mean I shouldn't consider traveling in avalanche terrain?  I know that everyone's process for risk assessment is different, but would you mind sharing a bit more detail on the specific stability tests that were done?


I am continually confounded by the vitriol spewed by people towards those with more risk tolerance.   I skied steeper terrain compared to another party that I shared the Tatoosh with on Sunday (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30932.0).  Am I an idiot or just less risk adverse?  We chose not to ski one particular north facing slope on that day, but what if another party decided to?  Are they fools that demand a little of the what for?  I know this has been discussed countless times, but the discussion always plays out the same way.  Experienced and knowledgeable backcountry skiers who went out last weekend knew the risks.  Some chose to take more risk while others chose less.  I don't believe that the ones choosing more risk deserve our reprimand. 

My thanks to the OP for his sharing his story.  Accident review is a very valuable tool.

I think it is worthy to make a point about the discussion, and not the avalanche itself.

You stated:
">>>>>>Lastly, in general, there doesn’t seem to be a community that allows for healthy conversation and debate for the purposes of education and safety. There is, what I hope, a small number of individuals that discourage reports such as this one with judgmental comments that don’t add to the conversation. I was encouraged to see a healthy discussion about the Chair Peak slide on TAY over the past few days (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30876.0). Although the conversation is mostly positive and educational, it also serves as an example of how there’s a small group of individuals who are not there to learn and understand."

"Healthy" is in the eye of the beholder and certainly any Internet discussion involves a number of commenters who should be ignored. But TAY and other discussion boards are actually a pretty good forum for learning and comments. But of course, you do have to be your own editor.

I say this from the background of having been on a guided trip in Canada where five out of six of us were caught in an avalanche. Amazingly, we had no injuries and the one person who was fully buried 1.5 m down survived the 13 minutes it took to eliminate the interference from the transmitters of all the partially buried people and then find him and dig him out.

I will not say what the organization was, but they are large and significant. The mere mention of my posting the details of the accident on a forum like TAY sent them into spasms and I had to "harass" the guide by email for four weeks after before he would actually post the event to the CAC website. Even then, he reported a slide much smaller than I remember and did his best to make the report fairly bland.

The slide and the recovery had some unusual aspects that would have provided good future lessons. It also occurred on a slope (which I discovered when I did my research once back in town) that is both commonly traveled and commonly unstable.

So our American system may not be the best, but at least we are willing to hash things out in public, even if it is unseemly at times.

I don't think the OP's party accepted more risk, they didn't appreciate the risk by their own admission. I'm not trying to judge them, it's what they put in their report.
author=blackdog102395 link=topic=30926.msg129593#msg129593 date=1393468599]
I am continually confounded by the vitriol spewed by people towards those with more risk tolerance.   I skied steeper terrain compared to another party that I shared the Tatoosh with on Sunday (http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30932.0).  Am I an idiot or just less risk adverse?  We chose not to ski one particular north facing slope on that day, but what if another party decided to?  Are they fools that demand a little of the what for?  I know this has been discussed countless times, but the discussion always plays out the same way.  Experienced and knowledgeable backcountry skiers who went out last weekend knew the risks.  Some chose to take more risk while others chose less.  I don't believe that the ones choosing more risk deserve our reprimand. 

My thanks to the OP for his sharing his story.  Accident review is a very valuable tool.

author=aaron_wright link=topic=30926.msg129598#msg129598 date=1393470136]
I don't think the OP's party accepted more risk, they didn't appreciate the risk by their own admission. I'm not trying to judge them, it's what they put in their report.


From the Conclusion section of the OPs report:

"In summary, I believe we followed our education and did many things right. We conducted our research and continued to communicate as we moved through the terrain. We observed that the conditions contradicted the NWAC forecast to some extent and believed moving forward was an acceptable risk for our party. Skiing in the BC is inherently risky. We do our best to stay safe, accepting a level of risk that is specific to each individual and group."

One lesson I am going to try to learn from this report is to make explicit what the Hazards Of The Day are, and no, these aren't  always avalanche. I believe this is now a prominent part of the AIARE I curriculum.  The involved party was looking for storm slab/wind slab, and was getting favorable signals on this front, but (in retrospect) the Hazard of the Day was deep slab.

In any case, I'm very glad that everyone ended up OK, and appreciate sharing the incident report. I will certainly keep my eyes out for gear if I make it onto the North slopes of Chair this year.


But what happened to them is exactly what the NWAC forecast warned about and they didn't appreciate that risk it seems. They claim the forecast was inaccurate.

author=blackdog102395 link=topic=30926.msg129600#msg129600 date=1393470472]
From the Conclusion section of the OPs report:

"In summary, I believe we followed our education and did many things right. We conducted our research and continued to communicate as we moved through the terrain. We observed that the conditions contradicted the NWAC forecast to some extent and believed moving forward was an acceptable risk for our party. Skiing in the BC is inherently risky. We do our best to stay safe, accepting a level of risk that is specific to each individual and group."

blackdog - I haven't noticed any vitriol on this thread; just healthy but as far as I can perceive respectful discussion, which at times can still be challenging in nature.

And I think Aaron is putting his finger on a key question any of us should ask about our own ventures - did this group understand the level of risk they were accepting with their route choice on this day? I don't know that we have all the evidence, but we have enough evidence to wonder. Again, I think this is mostly of interest WRT reflection on our own choices, as humans are apt to repeat each others' behaviors.

author=aaron_wright link=topic=30926.msg129602#msg129602 date=1393470724]
But what happened to them is exactly what the NWAC forecast warned about and they didn't appreciate that risk it seems. They claim the forecast was inaccurate.



Again, quoted from the report:

"I did my homework the night before to ensure I understood the conditions and risks. I reviewed NWAC, TAY, and consulted Topo maps despite the few years of experience I’ve had in the area."

If I take the OP at his word, I believe he knew the risks, including the risk of something deep and big breaking free, as he did his "homework" and "reviewed" NWAC.  

Black Dog wrote
author=blackdog102395 link=topic=30926.msg129593#msg129593 date=1393468599]
I don't believe that the ones choosing more risk deserve our reprimand. 

My thanks to the OP for his sharing his story.  Accident review is a very valuable tool.


Maybe your right. The climber choosing to go climb a hard route is looked up to rather than reprimanded.  Why does the skier have to choose the safe route or be  preached to?

Maybe it's skill versus simply risk taking? Skill is looked up to. Standing under a potentially deadly slope is not. If one guy had found a way to ski the North Face of Chair I'd have been impressed. For me, a skilled athlete taking risks is cool. I've read lots of books they've written! Skiing with others under a large, unpredictable objective hazard at a dangerous time is not. Maybe it's as simple as that.

Jim, I have found this thread respectful.  We all know that this is not always the case.  This thread for example contains a few choice posts:

http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30876.25

Many good posts here, thanks to the OP for contributing and making this a more meaningful review that is based on your account.


Cookie, I'm sure you only intended the best by your post, but it really strikes me as more of a indictment of the state of avy education then this particular party.  Your list is basically the "checklist" of criteria that AIARE and others have been pushing towards.  What you're saying is that the common thread of fatal avalanches is that parties involved appeared or believed they were following best practices of avalanche education.  Should we not follow these best practices and instead (as many anecdotes in this thread attest) trust our gut and ignore the signs and science?  While this can clearly work when a person's gut says "danger!", it has historically not worked when the message is "go for it".  


My take on the problem is that when there's a deep slab there are few if any tools available to reduce uncertainty in risk assessment.  If you're lucky you'll get natural failure observations, otherwise there's just time or evidence from other parties venturing out to convince oneself of a lowered risk.  Some people will wait for spring.  Some people will wait for a significant rain event, or a new formation of a thick hard layer that will provide bridging.  Others will accept a week or two of time as enough "proof" the snowpack has gotten stronger.  But really, until the spring cycle breaks this layer down, there will be some chance of deep failure.

We also don't really know if this was naturally or remotely triggered.  Many people travel beneath cornices or in other high risk areas for short spells, choosing to temporarily accept the potential but unlikely catastrophic risk of a cornice failure from above.  Deep slabs aren't all that common a problem in the PNW, and don't tend to be very predictable by nature.  

For reference, snowpack depths were doubled by the mid-February storm at some snotel sites.  The Chair Peak party chose to accept the perceived unlikely event of a deep slab failure.  NWAC presented it as possible, but not all that likely.  That's the kind of risk framing that some people are going to be comfortable with.  


Good post Trees.  It sums up our assessment on Sunday, especially this piece:

"For reference, snowpack depths were doubled by the mid-February storm at some snotel sites.  The Chair Peak party chose to accept the perceived unlikely event of a deep slab failure.  NWAC presented it as possible, but not all that likely.  That's the kind of risk framing that some people are going to be comfortable with."

As my partner and I traveled the north and south sides of the Tatoosh, we found a very consolidated snow pack with occasional sluffing of a storm layer on steeper north face aspects on the descent.  At one point, we discussed that if anything  more than the storm layer broke free, it would be really big as suggested by NWAC.    We understood the risk, deemed it possible, but not probable and continued ski these slopes, although we avoided the heavily corniced ridge.  We were comfortable with our assessment and the risk.  If we had gotten it wrong, and it went it big, would we have deserved criticism?

Thanks for posting your story.  I think we can all agree that the most important takeaway is that you and your partners are alive.  All the rest is incedental.

I was wondering about one thing: it looks like you might have been lost on your initial descent?  Looking at your map you went down only 400 ft while staying way too far to the right and then had to skin.  If that's the case and you were lost, it might have saved your life.  Crazy!  (Of course if you had made your way straight down to the lake, you might have been clear of the runout in time, but who knows.)

It does sound like you need to accept more personal responsibility in your adventures, but the key thing is that you get to keep having them!

I wish you guys good luck finding your gear.  I've lost two skis in the last five years and wasn't able to find them.  It can be surprising how difficult it can be to travel on ski lines without any snow.  Hopefully they are resting somewhere open and accessible, it's pretty easy for a ski to get swallowed by the underbrush.

Coming from an area of learning and discussion.

As I understand it the point of origin was 500 feet above where the skiers were.  What are peoples thoughts from this as a Naturally Triggered Slide, as was reported via the NWAC site http://www.nwac.us/observations/pk/101/?

My thought is  this is a human triggered slide, since the group was on the slide area and therefore loading the slope.  What do others think about this?


Kudos to shawnskis for posting such a thoughtful report. It's not easy putting yourself out in public like this. I hope you'll take my comments constructively.

In your original post, you wrote:

"We realized NWAC’s forecast was very different from what we were observing. There was no sign of natural or human triggered slides. While not completely ruling out the persistent slab, we felt comfortable pressing on."

It seems to me that the key lesson for all of us "coasties" (and I include myself in this) is that persistent deep slabs are really a different beast. The fact that you didn't observe any evidence of deep slab instability is COMPLETELY CONSISTENT with the NWAC forecast. When you say that the forecast was different from what you were observing, you can only have meant the near-surface instability. What you observed didn't (and couldn't) tell you much about the deep instability. This is also true of what your guide friend told you.

My suggestion is that you may have subconsciously transferred the apparent lack of surface instability into unwarranted confidence in the deep instability. I can imagine myself doing the same thing. It's not easy to separate them, but I think the lesson (to all of us) is that we need to do that.

I haven't bothered looking up the NWAC forecast for last Saturday, but it's worth noting what the current forecast says about the Persistent Deep Slab problem in the Snoqualmie Pass area (emphasis added by me):

Deep, persistent slabs are destructive and deadly events that can take months to stabilize. You can triggered them from well down in the avalanche path, and after dozens of tracks have crossed the slope. Give yourself a wide safety buffer to handle the uncertainty, potentially for the remainder of the season.

FYI for those reading this thread:

Last Saturday's forecast for Snoqualmie Pass actually didn't call out a persistent weak layer as a concern (wind slabs and storm slabs were).  Persistent weak layer was called out as a concern east of the crest.

http://www.nwac.us/avalanche-forecast/2014-02-22/cascade-west-snoqualmie-pass/

Thanks for pulling the link to the day's forecast, Susan. The January weak layer is only briefly mentioned at the top of the forecast discussion. However, near the end, I think this is the key sentence:

It will have been many days since there have been many people in the back country so conditions are a bit uncertain. Careful snow pack evaluation and caution should still be essential on Saturday.


As has been pointed out above, NWAC's forecasts are by necessity for broad, general areas; they are also not infallible. As Lowell mentioned, those of us who primarily deal with a maritime snowpack (forecasters included!) do not have a vast amount of experience with deep slab instability. These are the "black swans" of the avalanche world, especially in the coast ranges, so predicting the behavior of this particular avalanche dragon at the local/micro level is an awful lot to ask.

On the whole, this just reinforces the idea that unusual conditions require extraordinary caution. A persistent weak layer deeply buried under the rapid loading of 12 feet of new snow in two weeks is "out of sample" for most of our mental models of snow behavior in a maritime snowpack, and our usual approaches aren't going to give us the safety margin we might expect. It's one thing to know the risk and accept it, but I don't think we really can quantify or know the likelihood of the deep slab instability... most of us aren't in the habit of digging 12 feet down and doing a PST. Given that the consequences are so catastrophic, a given margin of safety just demands a totally different approach to terrain selection.

Awesome story and thanks for sharing. I was out taking risks during this last big cycle and could easily have had the same thing happen.  I actually believe some of your choices saved your butts.  I hope more folks write up reports like this one. The one thing I have learned there are no experts when it comes to avalanches.  Tremper was right.  At least I am not one.  Thanks.

Ok, given the forecast, weather history and terrain they still wound up where they got caught. When I say they didn't appreciate the risk, it's just like Jim said, they didn't fully understand the risk. So in my opinion they didn't assume more risk, they thought they were safer than they were. If this isn't so they report would read differently.

Again this isn't an indictment just an observation relevant to this conversation. I've put myself in similar spots before and gotten away with it.

author=blackdog102395 link=topic=30926.msg129604#msg129604 date=1393471456]
Again, quoted from the report:

"I did my homework the night before to ensure I understood the conditions and risks. I reviewed NWAC, TAY, and consulted Topo maps despite the few years of experience I’ve had in the area."

If I take the OP at his word, I believe he knew the risks, including the risk of something deep and big breaking free, as he did his "homework" and "reviewed" NWAC.  

Great trip report.

From what I see most of the comments are not negative but honest comments on how others assessed the avalanche hazard for that day/storm cycle. Everyone is trying to learn and apply what they learn in future ski trips. One thing is for sure, we had a huge storm cycle over that period of time. Huge storm cycles catch people off guard until they see enough of them.

Assessing stability is complicated, but in this storm cycle it was text book if you choose to read the signs.

• Up to 100” of snow fall in ten days
• Fluctuating freezing levels and high winds
• NWAC avalanche report for that storm cycle had fluctuated from considerable too High
• Other trip reports for that period had indicated many natural and skier triggered avalanches

Here is a great article about deep slabs…
http://www.avalanche.ca/uploads/decisionmaking/DM_AvalProbEssentials_DP_V1.0.pdf

author=bc_skier link=topic=30926.msg129635#msg129635 date=1393513561]Assessing stability is complicated, but in this storm cycle it was text book if you choose to read the signs.


author=trees4me link=topic=30926.msg129614#msg129614 date=1393472444]
Cookie, I'm sure you only intended the best by your post, but it really strikes me as more of a indictment of the state of avy education then this particular party.  Your list is basically the "checklist" of criteria that AIARE and others have been pushing towards.


author=trees4me link=topic=30926.msg129614#msg129614 date=1393472444]What you're saying is that the common thread of fatal avalanches is that parties involved appeared or believed they were following best practices of avalanche education.


You are exactly, exactly, exactly, exactly right. The parties involved appeared or believed they were following best practices of avalanche education. When in fact they most certainly were not following best practises at all. The point of my earlier remarks is that best practises cannot make up for fundamental errors, such as poor choice of objective. Best practises are put in place to help you avoid choosing an objective that is unsuitable for conditions. Everything else is just damage control.

Some people who posted trip reports in the same time frame clearly foresaw the potential for large avalanches and correctly extrapolated information from the public avalanche bulletin, along with their own observations, toward the worst case scenario ( Which is exactly the advice given in The Avalanche Handbook, AIARE, et al. ). With this information in mind, those parties demonstrated significant skill in both recognizing these conditions and having the discipline required to find appropriate terrain that included a generous margin of safety.

On the other hand, the reporter of this incident made sure we were all aware of his skills, education, and experience even while he described to us a trip that nearly resulted in three fatalities, a trip in which he took two novice backcountry skiers into alpine terrain known for producing large, destructive avalanches during a time when there was a reasonably foreseeable potential for large, destructive avalanches.

The description of this accident is sadly very typical: "we knew what we were doing; we're educated; we're experienced; our risk tolerance is different". If the purposes of this thread is to spread knowledge, then I feel perfectly comfortable saying that tour, as described, is an example of what not do, and there are other trips ( as I've noted ) that are great examples of how to tour safely in adverse conditions.

author=jj link=topic=30926.msg129585#msg129585 date=1393465400]All of these things (except perhaps the last two) are also mentioned in a large number of trip reports where there is no avalanche or injury.  I'm not sure how I would use those to differentiate a non-threatening situation from a threatening one.


My example was designed to show that many safe trips and unsafe trips sound the same until you look at the choice of objective and the attitude of the participants. Very often those two aspects are what differentiate threatening and non-threatening situations. I should have made that clearer. :)

^^^This is what I've been trying to convey but I lack Cookie's smarts.

author=aaron_wright link=topic=30926.msg129639#msg129639 date=1393515579]
^^^This is what I've been trying to convey but I lack Cookie's smarts.


I'd also like to chime in and say that Cookie's last post seems very constructive and also seems to lack malice.  I hope we all can read this type of post and take in the wisdom without being defensive.  All of us make mistakes.

Thanks to all for many wise words on this thread and others.  I've learned from a lot from the TAY community.

author=T. Eastman link=topic=30926.msg129576#msg129576 date=1393461960]

It hurts every time I read of severe injury or death where accustomed behavior directed the risk assessment and route choice.  Call it quarterbacking or "WTF" but I always appreciated being told bluntly by my peers or mentors that I had screwed up.   


You just have thicker skin Todd:)  My belief is that a large majority of the people involved in avalanches already know that they made a mistake.  The place for bluntness should come later, after there is an analysis of the incident.  "What happened" should take priority over "you screwed up" and "what were you thinking". 

author=Susan Ashlock link=topic=30926.msg129629#msg129629 date=1393485745]Last Saturday's forecast for Snoqualmie Pass actually didn't call out a persistent weak layer as a concern (wind slabs and storm slabs were).  Persistent weak layer was called out as a concern east of the crest.
http://www.nwac.us/avalanche-forecast/2014-02-22/cascade-west-snoqualmie-pass/


Thanks for pointing that out, Susan.

The NWAC bulletins have been talking about weak layers quite a bit, but mainly with respect to the eastern Cascades. It points to how limited our knowledge was following that big storm cycle and how cautious we have to be in "compartmentalizing" risks to a specific region.

It's interesting to look back at this thread from last Friday (2/21):

http://www.turns-all-year.com/skiing_snowboarding/trip_reports/index.php?topic=30842.0

The subject was the special avalanche warning for British Columbia. That warning and Karl Klassen's blog post that Charlie referenced went into much more detail on the potential for deep instability:

http://blogs.avalanche.ca/this-beauty-is-only-skin-deep/

It seems clear that in this case Klassen's advise was spot on. The excerpt that kerwinl pulled out is especially apt:

"Wait. Wait longer than usual before moving onto larger, more aggressive terrain. Some runs might have to wait for a couple of weeks or more. Some might be out for the rest of the season. This is especially important for all you folks in the coastal ranges where you’re used to waiting a few days to let things settle down, then going for it. The snowpack you’ve got out there, especially the south coast, is like nothing many of you have dealt with before. Don’t use your coastie tactics and expect them to work this season. You need to think more like the Interior or even the Rockies guys right now."


Klassen was absolutely right, and even NWAC wasn't entirely on top of this.

I have to say ALL OF US have been very lucky have this hazard demonstrated so vividly without anybody getting hurt. shawnskis should be thanked for bringing this discussion into the open by reporting his party's experience.

author=Susan Ashlock link=topic=30926.msg129629#msg129629 date=1393485745]
FYI for those reading this thread:

Last Saturday's forecast for Snoqualmie Pass actually didn't call out a persistent weak layer as a concern (wind slabs and storm slabs were).  Persistent weak layer was called out as a concern east of the crest.

http://www.nwac.us/avalanche-forecast/2014-02-22/cascade-west-snoqualmie-pass/


Chair Pk is not technically east of the crest. However due to Chair's position, topography, notches in the surrounding ridge, and it's summit; it assumes to the characteristics of being east of crest. IMO opinion, the conditions matched exactly with nwac's forecast. RE: the discussion of Chair vs. The Slot; the east side of Chair would more than likely be far more wind loaded than the Slot given the recent weather (wind)  patterns.

To to OP: Thanks you for having the balls to write this up. It is a valuable learning experience for all. Glad you made it back safe.

I think cookiemonster's post is right on.

author=Lowell_Skoog link=topic=30926.msg129649#msg129649 date=1393518800]I have to say ALL OF US have been very lucky have this hazard demonstrated so vividly without anybody getting hurt. shawnskis should be thanked for bringing this discussion into the open by reporting his party's experience.

Indeed. I hope we can still say this a week or three from now!

CookieMonster's analysis seems spot on to me. It probably reflects well what several of us have been trying to convey, but he communicates it much better.

His same analysis seems applicable to what I remember from the incident and analysis of the near-fatal event on Kendall from April, 2010.

The analysis, to my eyes, read largely as "we are guides, we are educated, this is what we did and why it was logical." It then ended with the smug  conclusion that "I seriously doubt that a normal, recreational group would have been able to pull off this rescue.", followed by a secondary admission that "They might not have continued above the trees either." (http://www.nwac.us/media/filer_public/ff/e5/ffe5bef7-d3de-42ce-8f5c-c798e363cf3c/kendall_peak_avalanche_accident_4-9-10.pdf)

I point this out because I think it's a good example to how much Cookie's list, just as he said, reflects what almost all accident reports seem to read as.

I'll also point to it as another example of my earlier point, that being a guide means little, and it means nothing to the mountains. It's a job title, nothing more. Put faith in the observations, logic and decision making of others, be them a guide or a McDonald's employee, at your risk.

Bottom line is we all make decisions on what's possible.  Backcountry touring is in many ways an exercise in probability.    Given the higher than normal possibility of a deep slab some will choose to ride low angle or clean their gutters.  Others will feel comfortable that possible, but not likely probable makes it "good to go."  I am in the first camp, but I understand those in the second camp.

The place for bluntness should come later, after there is an analysis of the incident.


Gregg, this is for all purposes, the analysis of the accident.  A formal report will be issued by folks that will write a dry, "what went down" set of observations.  The real deal is going on here in TAY where people are saying what they think, admitting to their own near misses, and describing their logic in their choices for dealing with deep persistent crap (DPC).  

There is a range of experience among the posters reflected in the comments.  Some of these people have considerable (I use the term with irony) experience with DPC.  This includes me.  From my perception, the message regarding travel during times of DPC here seems not to be as clearly understood as in in regions where it may dominate entire winters.  

Why is this? It is contained in the literature.  It is noted in conferences.  But, is it clearly and loudly proclaimed in this region's avi courses?  The ski community in this region is excellent at dealing with the upper layers that are where the hazards usually lurk, but dealing with DPC forces travel choices to occur well before being in the field and well before digging holes in the snow.  

TRs may also play an interesting role in the travel decision.  TRs for the most part are proof of not proving the negative in an environment where hazards exist but the skiers simply did not trigger an incident.  TRs are rarely formal reports but rather a mix of fun pictures, a few snow observations, and narrative crafted to reflect the writer's sensibilities.  TRs are fun but do they influence peoples ski plans?  Do TRs place an approval on a particular destination?  I don't know but as behavior is the issue in safe winter travel, such questions could be considered.

Interestingly we may see a relationship between the number of postings on threads in TAY and the probability of large catastrophic snow slides...

That question about TRs and how it influences people's sense of the risk level is an interesting and good one. And my thoughts on it are what led me to quote Lowell just above. It is a gift to the community to share info about the negatives in addition to the positives, including that it's a reminder that lack of negatives does not mean people weren't just getting lucky this time.

author=blackdog102395 link=topic=30926.msg129656#msg129656 date=1393521415]
Bottom line is we all make decisions on what's possible.  Backcountry touring is in many ways an exercise in probability.    Given the higher than normal possibility of a deep slab some will choose to ride low angle or clean their gutters.  Others will feel comfortable that possible, but not likely probable makes it "good to go."  I am in the first camp, but I understand those in the second camp.

If you truly understand the risks then that's a choice that puzzles me a bit, but it's yours to make. I believe some of us are seeing signs in this TR that the author did not really see the risks. E.g.
The snow seemed incredibly stable. On the switchbacks up to the saddle there was no sign of slide danger, nor any other slide debris. The snow layers seemed to have great cohesion. We realized NWAC’s forecast was very different from what we were observing. There was no sign of natural or human triggered slides. While not completely ruling out the persistent slab, we felt comfortable pressing on.

and
This leads me to discuss the information available on NWAC. The information provided by NWAC didn’t seem consistent with what we observed that day. NWAC forecasted human triggered slides as ‘considerable’ while from our account, they were extremely difficult to initiate. Also, naturally occurring slides weren’t mentioned in the NWAC forecast although we know that there was at least one.

The Considerable rating definition states that human triggered avalanches are likely and natural are possible. Some exceprts from the forecast discussion for the day (issued 8:35AM):
West northwest winds and light snow showers are decreasing on Friday. No new natural or human triggered avalanches have been reported so far on Friday. But winds on summits and ridges are locally strong enough (for example at the top of Crystal or White Pass) to build local wind slab on lee slopes on Friday.

and
It will have been many days since there have been many people in the back country so conditions are a bit uncertain. Careful snow pack evaluation and caution should still be essential on Saturday.


So there were two key things I assumed when going into the backcountry on Saturday:
1) wind loading particularly on E and SE aspects up high would be a concern, but there could be other aspects loaded depending on local winds and terrain (e.g. cross-loading). Skiing on or below such areas could be dodgy. I should add that a few miles to the SE, the ongoing wind transport during the day on Saturday was apparent.
2) despite the apparent stability of the deep snowpack, the confidence in that assessment was still not high (which is what led us into a very mellow choice despite all the green lights we were seeing en route)

Not to overly pick at shawnski's report, but those quotes raise a few questions for me. Was he concerned about potential for natural slides starting from wind loaded terrain far above his party, and did he discuss this with his partners? Given that they were on a very large known avalanche path, this would be an important realization for them to be truly aware of the risk they were entering into. Did he/they think about the possibility of something starting in the wind slab layer or a cornice drop up there and managing to get the deep slab going? (I'm just guessing this is what happened, though I suppose they may have remotely triggered this slide too...) They did not fully rule out the deep layer, but did they have confidence that the probability of it going was low, or did they believe that the probability was unclear (which is how I, conservatively, read the snowpack analysis from both Friday afternoon's report and Saturday morning's; and our group did not feel confident in our ability to really fully assess the risk level and thus reduce this uncertainty with an incredibly deep pit or two)? This question of understanding that we had a high degree of uncertainty about the probability of a slide (which is quite different from a low probability so if you happen to be in a slide we all say "you just happened to be in the wrong place" or "your number came up" or whatever) seems important for this day/period.

author=T. Eastman link=topic=30926.msg129658#msg129658 date=1393522158]
Gregg, this is for all purposes, the analysis of the accident.  A formal report will be issued by folks that will write a dry, "what went down" set of observations.  The real deal is going on here in TAY where people are saying what they think, admitting to their own near misses, and describing their logic in their choices for dealing with deep persistent crap (DPC).  

There is a range of experience among the posters reflected in the comments.  Some of these people have considerable (I use the term with irony) experience with DPC.  This includes me.  From my perception, the message regarding travel during times of DPC seems not to be as clearly understood in regions where it may dominate entire winters.  

Why is this? It is contained in the literature.  It is noted in conferences.  But, is it clearly and loudly proclaimed in this region's avi courses?  The ski community in this region is excellent at dealing with the upper layers that are where the hazards usually lurk, but dealing with DPC forces travel choices to occur well before being in the field and well before digging holes in the snow.  

TRs may also play an interesting role in the travel decision.  TRs for the most part are proof of not proving the negative in an environment where hazards exist but the skiers simply did not trigger an incident.  TRs are rarely formal reports but rather a mix of fun pictures, a few snow observations, and narrative crafted to reflect the writer's sensibilities.  TRs are fun but do they influence peoples ski plans?  Do TRs place an approval on a particular destination?  I don't know but as behavior is the issue in safe winter travel, such questions could be considered.

Interestingly we may see a relationship between the number of postings on threads in TAY and the probability of large catastrophic snow slides...

  I was referring to when the party has not published anything and folks weigh in without consideration for the groups need to digest the event free of negative feedback.  I have no trouble with this discussion.
I taught 5 courses this winter and all the instructors I was with definitely talked about the persistent layer and the potential for an event on this layer.  We emphasized dialing back the terrain considerably in the face of a difficult to interpret snowpack. 
Having worked with Karl K. over thirty years ago, I have a lot of respect for his insights and advice.  Given that I was out last weekend and had a great time with three clients while keeping the terrain well within my comfort zone.

http://coldthistle.blogspot.com/2014/02/deep-snow-skiing-on-modern-equipment-by.html

I was shocked to see all the tracks on the north side of Table however.  The skiing looked amazing but there was no way I would tread on that dragon's back given the uncertainty I felt about the snowpack.  (I feel about this snowpack the same as I did in 98/99)

Great discussion...love all the input.

author=kamtron link=topic=30926.msg129525#msg129525 date=1393438434]
When I saw the report from the Slot, 2 things crossed my mind:

1) Those lucky *****s! I bet the skiing was awesome.
2) That was not the kind of terrain I chose to be in on Saturday.

The Slot, more than any other serious tours I know, tends to get hit early after the storm. I think people are "getting away with it" more often that they might know. However, when we hear about the tours like this that go well, I think most of our reactions are first in category (1) because we know that everything went okay, and we wish we had gotten after it, too. People aren't going to be critical (especially on a forum like this) when things go well, because they don't want a reputation as a nay-sayer weenie-pants. I think the _lack_ of responses to the Slot post probably is due in part to the conflicting feelings people have between congratulating the party and wanting to warn them about the dice game their decision was.


Just wanted to highlight the above post, as I think it's a gem of truth.  At least, it read exactly like my thoughts.

Simply put:  

The leader made a conscious choice to put their party in a big slide path, underneath a massive loading zone soon after a huge snow/wind event, despite warnings.

This doesn't seem to be a matter of risk tolerance/acceptance; just recklessness, inexperience or ignorance.

I wonder if he/she would have made a similar choice if the hazard was more apparent and observable...such as the risk of avalanche due to springtime daily warming.

Gregg, thanks for you thoughts.  The winter landscape is so dynamic and at times inscrutable, but it keeps pulling us back...

... so off I go to ski.

So as it turns out the forecast DID NOT mention any deep instability at Chair Peak, but all of you wanna-be avalanche experts are castigating the OP for ignoring that guidance?  As I recall the NWAC forecast was "considerable" that day (just like it is pretty much every day there is good pow to ski).  There were no other natural slides in the area, and sluffs weren't stepping down.  Seems like a case of bad luck to me, as opposed to an obvious result of decision making errors, as presented by finger waving, self-righteous TAY mob.

You guys need to check yourselves. All of you have gotten lucky plenty of times.  Attributing your safety to your superior skills is the king of all heuristic traps (and pathetic).  Seems to me the point of the TR is to illustrate how even when you are doing "everything right" there can still be a substantial risk.  Thank you shawnskis for posting.  I appreciate the reminder. 

Nice report, glad everyone survived.

I'm not sure if this was mentioned, please forgive me if it was.

1. What is the avalanche education and BC Skiing experience level of the individuals in the group?  Maybe an opportunity to take some additional education?
2. Was there discussion of crossing the North aspect of Chair Peak with your guide friend or did the conversation only include the original and shorter plan?

Something new I learned from a short "refresher" avalanche course a couple of years ago is to read not only the current advisories but the previous 7-10 days of advisories when planning an outing, especially if there is a lot of new snow. This helps one to develop a better understanding of if there are deeper instabilities.

Thanks again for the detailed report, hopefully it will deter folks from making the same mistakes.

G2G, if you read the NWAC reports as the final word you would be correct, but there existed plenty of signs that DPC existed in the region (that there was old snow from early season sitting on top of soils and rock upon which boatloads of new snow was sitting...).  

NWAC should be part of a matrix and not depended upon as the sole base of one's decison making.  Regional trends do not count so much at the local level.

"You don't need a weatherman to see which way the wind blows..."

author=Good2Go link=topic=30926.msg129675#msg129675 date=1393530510]
So as it turns out the forecast DID NOT mention any deep instability at Chair Peak, but all of you wanna-be avalanche experts are castigating the OP for ignoring that guidance?  As I recall the NWAC forecast was "considerable" that day (just like it is pretty much every day there is good pow to ski).  There were no other natural slides in the area, and sluffs weren't stepping down.  Seems like a case of bad luck to me, as opposed to an obvious result of decision making errors, as presented by finger waving, self-righteous TAY mob.

You guys need to check yourselves. All of you have gotten lucky plenty of times.  Attributing your safety to your superior skills is the king of all heuristic traps (and pathetic).  Seems to me the point of the TR is to illustrate how even when you are doing "everything right" there can still be a substantial risk.  Thank you shawnskis for posting.  I appreciate the reminder. 

The forecast did discuss uncertainty about the snowpack, as I quoted. We all knew roughly how deep the snow from recent storm cycles was (or should have known!). Yes, I know I've gotten lucky plenty of times. No argument there. I will challenge you on the "superior skills" statement - I can't speak for others but a primary factor in choosing mellow lines for Saturday was due to my sense that my assessment skills are anything BUT superior, so given the high degree of uncertainty, but in my own head regarding how past mental models might apply to this unusual snowpack and given reinforcement by the very specific mention of uncertainty by NWAC, I chose not to push it by pretending I knew enough to get onto bigger steeper lines, let alone a frequently big avy path. This would push my risk level beyond my own comfort zone. shawnski and his group may truly have realized how risky a game they were playing but based on his report I'm left with the questions I noted above.

And was their luck bad or good?? If I put myself in their shoes, I'm thinking, on net, quite good!

My first exposure to avalanche risk mitigation was in Colorado.  Such an objective in that kind of snowpack, in midwinter, with a considerable rating, would be considered foolhardy.  

The Cascade snowpack is different, but after the winter you've had, the avy report and the storm conditions of the past week I think the objective was ill-advised.  

We should be cautious working backward from accident narratives to criticism. It's easy to see how this trip report could've been a jubilant one, with great skiing all day long. If the party had started an hour earlier, they'd have missed the slide almost entirely, perhaps not even seeing it until the return from Roosevelt. An hour later, and they'd have cool photos of the big slide and crown that appeared an hour before. Ten minutes earlier, and it'd have been worse.

A question shawnskis seems to be asking with his post is, "We thought we were doing everything right-enough, where in our decision-making did we go wrong? How can we all avoid that sort of error in the future?"  

The biggest thing that kept us from skiing velvety slide paths on Saturday was a feeling that we were out of our circle of competence when it came to instability evaluation. We don't know how to handle slope-scale stability evaluation of this much snow this fast, as much of our bag of tricks and experience doesn't apply at depth. That, along with the knowledge that there had been plenty of big slides and that persistent slabs were a concern a few miles away, if not at the pass, had us choose guaranteed-safe terrain. If I could offer thoughts for the future, it's to nibble at uncertain conditions, keep a margin of safety commensurate with uncertainty,  wait for conditions to be simple, then pounce.

Furthermore, NWAC stated greater-than-normal uncertainty in the discussion for the day -- nobody had enough information about the backcountry. Considerable was the right rating for Saturday - natural slides possible, triggered slides likely.




As "risk tolerance" has appeared above, a quick trip to the soapbox:

Risk tolerance requires acceptance of the downside outcome. It's a fact that you can do everything "correctly" and still get hurt, at any level of risk.

When we say that the upside is worth the downside, or "It's worth it", I don't think people understand downside risks until they've been experienced.

A certain tolerance for the outcome of disaster is required in the mountains, and in life.

Excellent TR.  Thank you for making the effort.  Glad it wasn't any worse than it was for everyone involved.

Couple of thoughts.

"Firstly, I learned that very well respected guides, were skiing with their clients on similar terrain last Saturday."

Which should make one realise no one has a perfect handle on this stuff.

I have been skiing Crystal and Alpental almost every day for the last two weeks. Some of it BC but not much intentionally.   Simply the amount of snow we have had recently and the extremely complicated terrain in the Alpental back country should make one extremely cautious. 

I think it is really hard to make your own snow safety decisions from the Internet and limited access to on sight field inspections.  Doing so in a huge storm cycle like we just saw is beyond most anyone, either from lack of experience or lack of education.   "Professional" or not.

There is an answer here.  Most just don't like it.  Including most of my partners.  Stay off complicated terrain until things settle down. (with all that implies)

Silly as it sounds, your life may depend on it.





author=Lowell_Skoog link=topic=30926.msg129649#msg129649 date=1393518800]

Klassen was absolutely right, and even NWAC wasn't entirely on top of this.

I have to say ALL OF US have been very lucky have this hazard demonstrated so vividly without anybody getting hurt. shawnskis should be thanked for bringing this discussion into the open by reporting his party's experience.


Absolutely!

Whether or not the Chair Party did things right or wrong, there trip has largely benefitted the PNW.  The writing is on the wall: 

THE CASCADES HAVE A VERY REAL DEEP PERSISTENT WEAKNESS THAT SHOULD BE TAKEN SERIOUSLY.

author=CookieMonster link=topic=30926.msg129637#msg129637 date=1393515252">
You are exactly, exactly, exactly, exactly right. The parties involved appeared or believed they were following best practices of avalanche education. When in fact they most certainly were not following best practises at all. The point of my earlier remarks is that best practises cannot make up for fundamental errors, such as poor choice of objective. Best practises are put in place to help you avoid choosing an objective that is unsuitable for conditions. Everything else is just damage control.

Some people who posted trip reports in the same time frame clearly foresaw the potential for large avalanches and correctly extrapolated information from the public avalanche bulletin, along with their own observations, toward the worst case scenario ( Which is exactly the advice given in The Avalanche Handbook, AIARE, et al. ). With this information in mind, those parties demonstrated significant skill in both recognizing these conditions and having the discipline required to find appropriate terrain that included a generous margin of safety.

On the other hand, the reporter of this incident made sure we were all aware of his skills, education, and experience even while he described to us a trip that nearly resulted in three fatalities, a trip in which he took two novice backcountry skiers into alpine terrain known for producing large, destructive avalanches during a time when there was a reasonably foreseeable potential for large, destructive avalanches.

The description of this accident is sadly very typical: "we knew what we were doing; we're educated; we're experienced; our risk tolerance is different". If the purposes of this thread is to spread knowledge, then I feel perfectly comfortable saying that tour, as described, is an example of what not do, and there are other trips ( as I've noted ) that are great examples of how to tour safely in adverse conditions.

My example was designed to show that many safe trips and unsafe trips sound the same until you look at the choice of objective and the attitude of the participants. Very often those two aspects are what differentiate threatening and non-threatening situations. I should have made that clearer. :)

Very good post, very constructive. The points made about experience level are very sobering, and reminded me of this paper put out in 2000 by Ian McCammon. This quote out of the summary is worth considering.

"Avalanche training did not appear to decrease the hazards
that groups exposed themselves to, and in the case of vic -
tims with basic training, hazard exposure actually
increased."


McCammon 2000

Shanski posted in the spirit of generating a healthy conversation. Again, thanks for doing so! In that spirit, I want to ask about this phrase from one of CookieMonster's posts:
...appropriate terrain that included a generous margin of safety...

What do folks think about this as a generally stated goal for the sort of terrain you'd want to be on this past weekend? Right on? Too much caution for you personally with the inclusion of the notion of "generous margin of safety?"

And how well do you think this particular route choice met this goal?

I think the statement is right on for that weekend, and the "generous" statement fits given the uncertainty.  As is evident from my other posts, I think the route choice comes nowhere near that.

author=kerwinl link=topic=30926.msg129684#msg129684 date=1393535569">
Very good post, very constructive. The points made about experience level are very sobering, and reminded me of this paper put out in 2000 by Ian McCammon. This quote out of the summary is worth considering.

"Avalanche training did not appear to decrease the hazards
that groups exposed themselves to, and in the case of vic -
tims with basic training, hazard exposure actually
increased."


McCammon 2000


Totally disagree. Cookie is miscasting the OP's basis for including their reasoning for being in that spot at that time in the TR, and even worse, describing it as "low skill".  And his tone is condescending.  If one of the best avy experts in world Ruedi Beglinger can't accurately predict the danger of a deeply buried instability, then certainly none of the folks on this string can either.  If the OP's group had skied the crap out of that line all day without incident, wouldn't it have been "higher skill" (i..e, a better understanding of the situation than NWAC and the experts on this string)?  If not, why? Isn't the whole purpose of avy education and NWAC forecasts to help inform us when it's safe to go?  If not, then why not just ignore it and ski 20 degree trees for the rest of your life?   (Seriously.)

BTW - All you wannabe experts, can I go ski that same slope right now, what with the "moderate" NWAC forecast and all, or should I still superimpose your higher level of skill to that guidance and stay clear?  (Not seriously.)
 

Go ski it....me, I would still wait a bit, and it would depend on recent weather conditions, time of day, etc.

I wonder what Ruedi would say he learned from that horrible accident.....poor bastard probably eats, sleeps and breathes it everyday of his life. 

Thought I would add to this since I was the one who posted the Slot trip report and I just saw this long series of comments.

First, i'm sure glad the three of you were not injuried and made it back safely.

Second, kudos for writing such an excellent report and to all others who have commented to make this an important lesson for all of us.

As to conditions in the Slot and why we decided to ski it, our thoughts, right or wrong, were that it would probably be okay for the following reasons:

In spite of the heavy recent snow, the slot sluffs off snow quite frequently because of it's rather steep slope.

It is also skied very frequently all year long, unlike the north side of chair peak.  This frequent skiing compacts the snow in the slot similar to a lift ski area and because it is narrow, most of the slot gets compacted.  At the same time, this frequent skiing brings down a lot of the loose surface snow.

And since it is so protected, wind loading shouldn't be an issue in there.

In addition, someone had just skied the slot, solo, before us.  we actually thought this was rather risky to be heading up there alone on such a day.

We also noticed very stable conditions in the upper surfaces as noted by many people.  What we didn't properly assess was the deep instability that existed.  however, with all the skiing in the slot, does this still exist there?  Without digging a deep pit we won't know.

The area where we knew we were treading lightly was getting to the Slot after coming out of the trees.  We kept a fair distance from each other but we were discussing it as we skinned up.  No question, this is the area that made us most nervous and we almost turned back.

Just trying to add to the conversation as to why we chose to ski the slot.  Maybe we got lucky, maybe it was stable because of the reasons i noted.

However, from all the excellent comments made by others, I will choose more wisely in the future.

I don't know if I've ever heard Ruedi described as "one of the best avalanche experts in the world".  I don't think anyone here has claimed to be an expert, most, including myself, realize we aren't so would exercise a bit more self discipline and restraint. A lot of the folks posting here likely have decades more experience than the OP. Even if the NWAC completely omitted and mention of PWLs and deep slab instability, they  certainly mentioned wind and storm slabs on high ridgelines which is what caught this group.

You seem to have some personal investment with this topic given your emotional and somewhat irrational responses.

author=Good2Go link=topic=30926.msg129688#msg129688 date=1393539454]
Totally disagree. Cookie is miscasting the OP's basis for including their reasoning for being in that spot at that time in the TR, and even worse, describing it as "low skill".  And his tone is condescending.  If one of the best avy experts in world Ruedi Beglinger can't accurately predict the danger of a deeply buried instability, then certainly none of the folks on this string can either.  If the OP's group had skied the crap out of that line all day without incident, wouldn't it have been "higher skill" (i..e, a better understanding of the situation than NWAC and the experts on this string)?  If not, why? Isn't the whole purpose of avy education and NWAC forecasts to help inform us when it's safe to go?  If not, then why not just ignore it and ski 20 degree trees for the rest of your life?   (Seriously.)

BTW - All you wannabe experts, can I go ski that same slope right now, what with the "moderate" NWAC forecast and all, or should I still superimpose your higher level of skill to that guidance and stay clear?  (Not seriously.)
 

Thanks for chiming in on your reasons for skiing the slot. I agree that exiting the treelike is where the first bit of concern would be for me on that route in these conditions but I would also have had reservations about the exit after skiing the slot.

I wonder if persistent weak layer is the right term for the slide we are talking about. In my mind it was all one big storm system and rather than looking at it differently from a trickier continental snowpack mindset I just viewed it all as a big dump that although settling enough to make trail breaking easier as time went on was far from bonded or bridged. I think labeling this as pwl is lending to much mystery to it rather than in terms of our normal multi foot storms where one expects natural releases and knows to use caution. I don't have the official definition memorized but I would tend to reserve pwl for something that lasted more than a storm.

Cookie's comment that the party was "most certainly not following best practises at all," seems completely out of line.  In fact they did many things right: pre-trip research, equipped with appropriate gear, discussion of the conditions, safe travel in avalanche country, transitioning in a protected area.  In fact, the decision to transition on an intentionally chosen terrain island was likely what prevented injury.  I shudder to think that most of the terrain islands I choose wouldn't come anywhere close to protecting me from a slide with a 10 foot crown running more than a thousand feet.

The only major error I can see (and only in retrospect) was incorrect evaluation of the deep layer risk on the terrain they chose to travel on.  As many have mentioned evaluating deep persistent layers is challenging even for well trained backcountry travelers.  This will certainly be a recurring topic over the coming weeks.  Is the deep persistent layer "safe" now?  If not, when will it be?  Those answers will be different for everyone and depend on little more than individual risk tolerance.

author=Good2Go link=topic=30926.msg129688#msg129688 date=1393539454]
Totally disagree. Cookie is miscasting the OP's basis for including their reasoning for being in that spot at that time in the TR, and even worse, describing it as "low skill".  And his tone is condescending.  If one of the best avy experts in world Ruedi Beglinger can't accurately predict the danger of a deeply buried instability, then certainly none of the folks on this string can either.  If the OP's group had skied the crap out of that line all day without incident, wouldn't it have been "higher skill" (i..e, a better understanding of the situation than NWAC and the experts on this string)?  If not, why? Isn't the whole purpose of avy education and NWAC forecasts to help inform us when it's safe to go?  If not, then why not just ignore it and ski 20 degree trees for the rest of your life?   (Seriously.)

BTW - All you wannabe experts, can I go ski that same slope right now, what with the "moderate" NWAC forecast and all, or should I still superimpose your higher level of skill to that guidance and stay clear?  (Not seriously.)
 

-Nobody claimed to be able to predict the danger of the PWL, that is point multiple people have made. A persistent weak layer is fickle enough, that even those with many hours/days of dealing with such layers have an inability to predict behavior with any accuracy.
-If the OP's group had skied the slope several times without incident it does not mean that they would have had "higher skill". Exposing yourself to very small probability of a catastrophic event over time will lead towards harm/death over repeated exposure, no matter how "skilled" the party is. Experts get killed in the same avalanches that kill novices, it is not a matter of skill, it is a matter of taking a chance.
-The purpose of education/nwac forecast is to help inform us of the current situation, but it is only a start. The forecast or our training can never tell us that it is safe travel any slope, it is merely a starting point to be followed by good decision making in the field.
-There is an assumption in that people with high levels of expertise are more conservative, then those with low levels of skills, which is not true, as evidenced by the paper I linked earlier. Some people myself included without years and years of experience simply choose not to take chances and ski in areas that have catastrophic consequences if an event occurs, I would not conflate that risk aversion to high skill.

author=aaron_wright link=topic=30926.msg129695#msg129695 date=1393544157]
I don't know if I've ever heard Ruedi described as "one of the best avalanche experts in the world".  I don't think anyone here has claimed to be an expert, most, including myself, realize we aren't so would exercise a bit more self discipline and restraint. A lot of the folks posting here likely have decades more experience than the OP. Even if the NWAC completely omitted and mention of PWLs and deep slab instability, they  certainly mentioned wind and storm slabs on high ridgelines which is what caught this group.

You seem to have some personal investment with this topic given your emotional and somewhat irrational responses.



Emotional? irrational? I got a good laugh out of that, thanks.  As much as I'd like to engage in a personal battle with you Aaron, I don't have any skin in this game. I just think it's counterproductive to pontificate and condescend when somebody is retelling a story about a mistakes in judgment, especially when they thought they were following "best practices".  You (and Cookie and the rest) could have made your point by simply saying that when there's enough uncertainty, you choose to ski in conservative spots. Anybody reading this string would have then clearly understood your point (and received the benefits of your "wisdom").  Instead, you chose to critique the OP's choices as though he was saying he would do it all the same way again, when what he was actually saying (IMO) is that those choices were insufficient under the circumstances, and lead him to the wrong conclusions. Now, instead of attacking me, how about you turn your venom on that guy who posted about skiing the Slot?  He seemed insufficiently recalcitrant by TAY standards, don't you think?

Thanks for your perspective, snowdog. As others have said, this thread is of great value IMO. I encourage the OP to respond; I hope he/she feels comfortable coming back.

author=Charlie Hagedorn link=topic=30926.msg129681#msg129681 date=1393532454]
We should be cautious working backward from accident narratives to criticism.


I wanted to add my voice to those empathizing with the OP. I heartily agree with many of the critiques, but I think some of the criticisms have been delivered with some condescension. This may have been in response to perceived hubris in the original post. I think it was not hubris but defensiveness, and I would encourage the community to read the trip report generously, taking into account the awkwardness and difficulty of recounting a trip in which your party was caught in a large avalanche. I would like to think I would not find myself caught in a slide such as this one, but it only takes one misjudgment or lapse of vigilance to find yourself in a bad spot. So please take my ramblings below as constructive (they are intended to be so).

I think this party missed the forest for the trees, and I wonder if this is not a danger of avalanche education. Lots of information was considered (NWAC, reports from the guide friend, the party's own observations on the trip, etc.). But for this hazard all the relevant information is contained in the observation that a shitload of snow had fallen continuously over the preceding two weeks. A simple rule of "don't ski over 30° within a week of a big storm" would have been worth more than your L2 avalanche class. Or, to say it another way, sometimes the inspection of a variety of data leads us to underestimate the uncertainty in our final evaluations.

I often hear things like 'your snow assessment should not be used to provide evidence of stability only evidence of instability.' While I appreciate the sentiment, I think this is an operationally meaningless statement -- the absence of evidence of (serious) instability will yield a decision ski just as evidence of stability would have.

I would like to thank Shawnskis for his very brave, very important, most excellent and valuable post.

I do not have alot to add to "the meat" of this thread, but can offer some personal experience in regards to *Guide is pronounced "guide", not "god."
I was instructed by an experienced Canadian Mountain Ski guide to "follow my traverse and ski right of the tracks"
Well I did just that and triggered a slab with 3-4 foot crown which ran down the designated ski run and  knocked over another client below (no one hurt, but they did infer that I was to blame in the hut debriefing afterward. The CMS guides are awesomly good, it was a rare event)   

A second thought sticks out in my digestion of the thread-
I was very impressed by, and wanted to re post the quote from the special BC avi statement-

"Wait. Wait longer than usual before moving onto larger, more aggressive terrain. Some runs might have to wait for a couple of weeks or more. Some might be out for the rest of the season. This is especially important for all you folks in the coastal ranges where you’re used to waiting a few days to let things settle down, then going for it. The snowpack you’ve got out there, especially the south coast, is like nothing many of you have dealt with before. Don’t use your coastie tactics and expect them to work this season. You need to think more like the Interior or even the Rockies guys right now." 

A third maybe helpful thought, perhaps discussed here before?
The slot couloir part of the thread relates to what I refer to as the "TAY heuristic". Something I feel effects us all here at TAY.  TAY provides familiarity and we see posts from folks in all kinds of conditions which can perhaps lead us to a "those guys did it" thought pattern.

Anyway, kudos to all for a very thought provoking and mostly respectful thread.




Close to a decade ago I wrote a TR on TAY about skiing Snoqualmie MT solo one morning, and created a nice flurry of internet fodder for the choices made re: avalanche safety, hydration and general incompetency.  I'm actually very impressed by the growth and depth of the responses here, generally.

Nothing much changes, yet everything changes.  Thanks for talking about your experience. I, too, have Tripped the White Fandango and am lucky to be alive.

Life is long, hopefully, and learning from it ensures its longevity.

I think all of the conversation is interesting regarding evaluation, overestimating abilities etc.   The big variable here is we are simply not used to this continental type of persistent deep/weak layer here in this maritime climate.   All of the OPs original assessment and evaluations would apply on 9 out of 10 years and cover the spectrum of risks, but the threat of a catastrophic all-cuts-loose event was clearly not deemed a threat.   And at this point, it is so far down you can dig a 5 or 6' pit and not hit it. 
Would be an interesting study to have a core sampling tool to be able to extract a column of snow from the snowpack at various locations/elevations/exposures and see how variable that PDL is.

author=RonL link=topic=30926.msg129697#msg129697 date=1393545144]
I wonder if persistent weak layer is the right term for the slide we are talking about. In my mind it was all one big storm system and rather than looking at it differently from a trickier continental snowpack mindset I just viewed it all as a big dump that although settling enough to make trail breaking easier as time went on was far from bonded or bridged. I think labeling this as pwl is lending to much mystery to it rather than in terms of our normal multi foot storms where one expects natural releases and knows to use caution. I don't have the official definition memorized but I would tend to reserve pwl for something that lasted more than a storm.


I agree with you, Ron.  Good description....  not sure PWL is what I would call it.

author=RonL link=topic=30926.msg129697#msg129697 date=1393545144]
I wonder if persistent weak layer is the right term for the slide we are talking about. In my mind it was all one big storm system and rather than looking at it differently from a trickier continental snowpack mindset I just viewed it all as a big dump that although settling enough to make trail breaking easier as time went on was far from bonded or bridged. I think labeling this as pwl is lending to much mystery to it rather than in terms of our normal multi foot storms where one expects natural releases and knows to use caution. I don't have the official definition memorized but I would tend to reserve pwl for something that lasted more than a storm.


The key, I think, is what happened BEFORE the big storm.

Think about the winter we've had. Months of below normal snow depth. Killer crusts formed in January, some new snow, then many days of sustained frigid weather (below zero F in many places). Then we got the big dump.

I'm just going from memory. Feel free to provide more detail.

That is not a typical Cascade weather scenario. If you'd like to bet your life that the layers underneath the 12+ feet of snow we received in February are just normal coastal snow layers, that's your privilege. If you bet wrong, I guess that's just "bad luck" (in Good2Go's words).

But it seems like a bad bet to me.

I'm going to assume there is a persistent weak layer out there and behave accordingly.

Makes sense, you guys both make good points....I guess time will tell if it is "persistent" and continues to be "weak".  But I think your "assumption" and associated plan is a good one.   

author=DaneBurns link=topic=30926.msg129682#msg129682 date=1393533478]
Excellent TR.  Thank you for making the effort.  Glad it wasn't any worse than it was for everyone involved.

Couple of thoughts.

"Firstly, no one has a perfect handle on this stuff.

 Simply the amount of snow we have had recently and the extremely complicated terrain in the Alpental back country should make one extremely cautious. 

I think it is really hard to make your own snow safety decisions from the Internet and limited access to on sight field inspections.  Doing so in a huge storm cycle like we just saw is beyond most anyone, either from lack of experience or lack of education.   "Professional" or not.

There is an answer here.  Most just don't like it.  Including most of my partners.  Stay off complicated terrain until things settle down. (with all that implies)

Silly as it sounds, your life may depend on it.

they got lucky.
b

Lowell, I am not going to take that bet, and I didn't that weekend. I am making the distintion because I think the label of pwl and all the attention that accompanies it gets applied too late for the incident at hand and likening it to continental regions is a bit vague to people not accustom to them. Whereas using the rule of thumb of being cautious after a big storm in the maritime climate can be applied before we get the kind of confirmation needed to call it a pwl. I would rather the summary of what went wrong focus on the aspects of this large amount of new snow will settle enough to give you some evidence of surface stability but it may not be the sort of stability strong enough to bridge the old storm layer regardless of whether that storm layer is just some old garden variety maritime crust or something that resembles the elevations and dyness of the Rockies. Time will tell if it was persistent but it was obviously deep and it failed. Perhaps someone will discover something truly unique about the snow down there but if they don't it may just point to ten feet of new has the potential to go big on many different types of crust that we often get in the nw and big steep open terrain should have a known warning on it.

author=RonL link=topic=30926.msg129758#msg129758 date=1393626440]
I am making the distintion because I think the label of pwl and all the attention that accompanies it gets applied too late for the incident at hand and likening it to continental regions is a bit vague to people not accustom to them. Whereas using the rule of thumb of being cautious after a big storm in the maritime climate can be applied before we get the kind of confirmation needed to call it a pwl. I would rather the summary of what went wrong focus on the aspects of this large amount of new snow will settle enough to give you some evidence of surface stability but it may not be the sort of stability strong enough to bridge the old storm layer regardless of whether that storm layer is just some old garden variety maritime crust or something that resembles the elevations and dyness of the Rockies. Time will tell if it was persistent but it was obviously deep and it failed. Perhaps someone will discover something truly unique about the snow down there but if they don't it may just point to ten feet of new has the potential to go big on many different types of crust that we often get in the nw and big steep open terrain should have a known warning on it.


Sounds fair, I guess.

If I understand you, you're reluctant to use the word "persistent" because it's too soon to do so.

I can go along with that. Instead, how about calling it a "Big Hairy Question Mark." It seems to me that's what it is. We can each decide how to deal with it.

I think it would be a mistake, however, to just forget about what happened before the big dump because it is now buried under several meters of snow. That's just willful amnesia. The snow doesn't forget. We shouldn't either.


author=RonL link=topic=30926.msg129758#msg129758 date=1393626440]
Perhaps someone will discover something truly unique about the snow down there but if they don't it may just point to ten feet of new has the potential to go big on many different types of crust that we often get in the nw and big steep open terrain should have a known warning on it.


After thinking about it a bit more, I see that your real point was that regardless of whether there was a funky layer down there, heading for the north side of Chair Peak (or the Slot Couloir for that matter) right after a big dump like that is a questionable call. I agree.

author=Lowell_Skoog link=topic=30926.msg129760#msg129760 date=1393628701]
Sounds fair, I guess.

If I understand you, you're reluctant to use the word "persistent" because it's too soon to do so.

I can go along with that. Instead, how about calling it a "Big Hairy Question Mark." It seems to me that's what it is. We can each decide how to deal with it.

I think it would be a mistake, however, to just forget about what happened before the big dump because it is now buried under several meters of snow. That's just willful amnesia. The snow doesn't forget. We shouldn't either.



How about we call it a "giant f**king windslab" that would probably be most accurate.

Actually, in the context of preplanning for a trip I do prefer big hairy question mark. I agree with incorporating the weather leading up to the storm too but I think if anything it makes the question mark hairier. I guess I am focusing more on why nwac and people in their trip reports and other sources people look to in preplanning might not be able to give a clear warning about this incident but other sources such as the prestorm weather, the amount of new snow, the lack of a big change in temps and no big bridging layer provide a big hairy question mark that should over ride the percieved green light a considerable rating, a couple surface stability tests, and other successful trip reports may have given one. I was just reacting to the thread drifting toward a pwl being the culprit and shifting the focus of off what could have been foreseen especially if after digging down ten feet and sweating like ski bum with his first mortgage one were to find no clear uniquely bad layer. That is way too much typing on a phone for now.


A cornice(or something large) was likely dislodged off Chair peak transferring enough energy and force to react the PWL on the face below.

This is consistent with that days forecast, the slide path and similar behavior was observed on the Alpental ridge in that same time period and on a related aspect. This is observable to any one who takes a moment to look out the high-gate.

It is unlikely that the skiers remotely triggered this specific slide since if that were the case we would have observed a much more active slide cycle during the storm and that simply hasn't been the case.

That PWL is there. It's in the slot as well which is an assumption I make but I think a likely one. Less sun exposed areas had the strongest crust and sandwiched faceted layers prior to the storm cycle. It will take some force to react that layer but it can be done in weird ways at weird times. That is the point of calling out a weak layer. They are hard to forecast and un-predictable.

I wouldn't be too terribly harsh on those skiers. In colorado if a PWL forecast meant not skiing BC then you wouldn't ski BC all year, every year. Know that this layer is out there. This is the risk you assume when you travel right now.

my 2c

author=RonL link=topic=30926.msg129758#msg129758 date=1393626440]
...likening it to continental regions is a bit vague to people not accustom to them.......

IMHO, if you are going to go into the backcountry you should be paying attention to the conditions from just before the first snow flies to when you are going out. So even if a person is not aware that may be the norm in the Rockies that doesn't (and mother nature won't) give them a free pass. Anyone that has read a book or taken a class on avy/snow condition awareness should be including that in their assessment.

The OP said he "did his research" but did not elaborate so whether / how much this variable was considered is unknown.  I would be interested to know the OPs thoughts on if he assessed what that early layer may pose as a risk. If he commented in the last 5 pages on that I missed it so apoligize in advance if that is the case.

The other thing is, you see a bunch of tracks or TRs, or talk to guides etc. that were in the same area that affects your decision making for sure. Someone else was already there and was the guinea pig...

I can't believe you're blaming nwac for your own mistake.



edit:  to change stupidity into mistake, as this is tay and we all have to play nice.

At this point I don't think we can call what it slid on a PWL. The key to a PWL is that it is persistent, hence it doesn't go away, it persists.

I agree that I think what happened here was the entire new 2 week storm(s) slid on the light, dry, weak layer that was ontop of the rain crust.

All that happened here was a typical avalanche scenario, just magnified by the unusual amount of new snow: Crust, followed by a very cold storm= light, dry, uncohesive snow=weak layer on slick bed surface. Then you introduce multiple heavy warm storms, and wind, you get a massive slab on top of the weak layer. The perfect recipe for an avalanche. It's right out of the textbook.

The only difference here than the normal scenario is the amount of snow. A skier probably wouldn't trigger it, unless they hit a shallow spot and it propagated. But the weight of a falling cornice could, or maybe it was just at the tipping point. Who knows.

What I do know, is that I've been on way hairier spots than this on considerable days, but I wasn't going anywhere even close to that level of terrain given the recent weather events leading up to it.

What I think happened here, was a classic case of looking for green lights, and not recognizing the blazing red flags. And not that I haven't done it, just not this time.

Now if someone digs down a week or two from now and that layer hasn't stabilized, then I would  consider the layer persistent.

is a rattlesnake just a snake until it rattles, or is it a rattlesnake because it has the capacity to rattle?

author=z-bo link=topic=30926.msg129772#msg129772 date=1393637704]
I can't believe you're blaming nwac for your own mistake.



edit:  to change stupidity into mistake, as this is tay and we all have to play nice.


Thanks z-bo.

This is a very good discussion.  Thanks for starting it and thanks to all of those sharing their thoughts and emotions.  For sure, all of these are factors in our decision making and it is helpful to get them out into the open.

"Experience"  What do we mean by that?  How relevant is it to our decision making?  It seems like either we think we have more than we do, and so we are foolishly confident.  Or, we become more conservative over time?  A friend of mine in my field, who has many more years of experience than I, once advised me to "Know your limits."  I have been puzzled by that ever since.  I wish I knew my limits.  How can I know them until I reach them?  And when I do, what are the consequences?  If I'm lucky, then perhaps I learn and move on to more experience and a better understanding of my limits.  But if I don't push my limits, will I ever grow or increase my skill?

"Considerable"  When I read this, I question whether I should even be out there.  Human triggered avalanches are likely.  Conservative and careful terrain selection are essential.  *If* I go out on a considerable day, I seek terrain that I understand to be safer.  Trees.  Low angle.  Away from open slopes.  However, I know that over this very weekend I ventured into higher angled terrain then I expected I would.  We were comforted by the stability of the surface layers.  We consoled ourselves with the tests we were familiar with.  We were in somewhat treed terrain with some openings.  Nothing seemed huge.  This conversation will hopefully help me keep it all in check a bit better when the stoke is high.

"Terrain Selection."  That is really the only thing we have any control over besides the choice to go or not.  I believe the OP did their very best.  How were they to know their limits in their knowledge or to sense the weakness in their strategy until they came up against it?  I suppose that is why it is so essential that we share with one another our experiences and our limitations.  I personally would never have chosen to approach chair peak over this weekend… and certainly will still be avoiding it and similar terrain. It is huge and the consequences are "catastrophic."  For me, it is a personal rule to avoid this kind of terrain until the spring when there is predictable melt freeze cycles and consolidated snow to the ground.  But that is my own personal rule and I don't hold others by it.   It just helps me when I get tempted.  I really appreciate Charlie's TR on the terrain they selected and why.  That helps me formulate better rules for myself.

Persistent Weak Layer or the Big Hairy Question Mark:  I grew up in the Wasatch front and am familiar with this problem--In fact, when I moved to the PNW I thought NWAC never really did any real observations because the Forecast was so often "moderate."  It just didn't seem possible that it could be moderate for so long and there was no PWL to be worried about.  However, I knew the PWL would be a problem this winter from my early season tours--as Lowell reminded us; nasty curst, little snow, super cold…  then layer upon layer of snow.  I think the advice to "wait" is excellent.  At least for certain kinds of terrain.  The late spring and early summer can change everything.  Besides, the days are long and for me, this is the best skiing to be had all year.  It is the time of year to really explore the alpine on skis.

NWAC and forecasting.  The PNW is riddled with mountain ranges upon mountain ranges.  I mean, the Olympics alone are vast and I believe we only get data from one isolated location.  The weather is crazy difficult to forecast.  Varying climate zones.  Compare this to the Utah Avalanche Center.  There does seem to be more data shared from users and professionals out there.  Perhaps there is more funding.  But, the mountain ranges are smaller.  The Wasatch Front in the Salt Lake area is about the size of the Picket Range.  Yet it is riddled with skiers making observations and sharing information.  Whenever an avalanche occurs there is almost immediate data and reports with handy maps and photos.  I wish NWAC had this feature… but I realize the logistics of reporting and gathering data for the entire WA Cascade range and the Olympics is seriously complex.  It would be nice if there was an easy way to post observations while out there.  Perhaps there is and I'm unaware.   It behooves us all to make a contribution to NWAC and to provide feedback.  

author=powhound link=topic=30926.msg129782#msg129782 date=1393644397]
Now if someone digs down a week or two from now and that layer hasn't stabilized, then I would  consider the layer persistent.


Good luck performing that test.   ;)


I've posed this question in my last two posts and no one will bite.  So I'm going to bluntly call everyone out.  It seems we all agree that there's a persistent weak layer (or whatever you prefer to call it).  When will you be comfortable to ski routes like Chair (or similar terrain) given that knowledge?

The only person that seems willing to commit to an answer is danpeck who says he will wait until spring -- I can respect that.

Here's the way I look at this issue.  There was a moment in time when the last flake fell in the previous storm cycle and danger was at some baseline.  Since then it's varied from that baseline.  Generally speaking it tends to fall over time as intra-snowpack temperatures equalize and layers bond and natural slides take place.  However, sun and high temps may cause it to increase at various points due to cornice collapses and other factors.  The probability of a slide was never 100% and it will never be 0%.

The only meaningful issue people seem to be debating is whether the group was in the particular terrain too soon.    So when will it be reasonable to be on that terrain in your opinion?  In my mind you don't get to armchair quarterback someone else's decision if you aren't willing to commit to your own decision.

author=jj link=topic=30926.msg129797#msg129797 date=1393663808]
The only meaningful issue people seem to be debating is whether the group was in the particular terrain too soon.    So when will it be reasonable to be on that terrain in your opinion?  In my mind you don't get to armchair quarterback someone else's decision if you aren't willing to commit to your own decision.


I'm going to wait. I don't know how long yet. Seems like the backcountry skiing is probably crap right now, so there's no hurry.

I'm planning to get more lift skiing in during the next few weeks, having stayed away during the snow drought. I'll also continue my regular skimo workouts.

I'll be watching trip reports and avalanche reports closely. In other words, "Looks good. You go first." I've got no problem hanging back to see what other people find. Play the long game.

I'm going to be wary of big temperature or snow load changes. When we get the first "big warm up" in spring, I'm not going to rush out there. The arrival of spring will be no panacea if it arrives too fast!

I'll be looking for cool weather with a light new snow load.

Basically, I'll be playing it by ear and enjoying other ski activities for a while. I don't need to (and I'm not able to) go backcountry skiing every week. So I'm happy to just play it by ear.

If you're not satisfied with a tentative and non-committal answer, that's not my problem.

author=jj link=topic=30926.msg129797#msg129797 date=1393663808]
  When will you be comfortable to ski routes like Chair (or similar terrain) given that knowledge?

The only person that seems willing to commit to an answer is danpeck who says he will wait until spring -- I can respect that.



Like Lowell, I'm unable to go into the BC every week.  I wish I could and perhaps that day will come.  However, if I had the choice… I guess I feel like this question is loaded.  So much to think about.  Spring isn't the solution… as Lowell points out, it can bring it's own set of new problems.  Reading the article NWAC linked to on PDS's gives the impression that it is simply very difficult to have any real sense of predictability here.  Triggering a PDS is highly unlikely by a skier. But other factors complicate this.  Cornice fall.  Small surface avy's stepping down.  Rapid temperature changes.  Rain events. 

I suppose if someone were out there digging 2 meter pits that would be helpful.  Or, if there was slide activity out there exposing the PDS that could also help. 

Snoq. Pass has some of the most extreme alpine terrain out there.  Chair Peak is in a wild zone.  I guess for me, if NWAC continued to call out the threat of the PDS, then I would probably wait until late spring or early summer.  There are plenty of other options out there in the meantime…  even alpine options.

Another huge factor would be the travel route.  There are ways to get into areas or peaks like Chair that offer a safe approach and exit.  I love traverses in the Spring partly because of the stabilizing snow pack but also because there are often several options for route selection and the route will change based on the specific threat.  It is also true that some routes will simply remain unsafe for an entire season.  PDS's can linger into August!

This has been an odd winter.  It makes sense to make it a conservative year.  I have plans for a multi day trip in late May or early June and where I go and what we accomplish will be determined by this among many other factors. 

Today, the threat on NWAC is moderate.  Perhaps the fun is to be had in N facing glades and bowls and couloirs that do not have such big terrain features and consequences.  I like Tremper's writing on this… always think about the consequences.  "If this section goes, what will it be like?  Can I manage this?"

So… I guess my answer is I'm going to wait.  Especially through March and April when conditions can be especially schizophrenic between winter and spring/warm conditions.  That doesn't mean I'm not going to go into the BC.  It just means I'm going to avoid big faces like Chair.

Please critique my thoughts.  This is a valuable exercise for me.

Edit:

Many objective hazards in the alpine are sort of freakish… such as serrac fall or rock fall.  The risk can be mitigated by speed of travel and the time of day.  Perhaps something similar can be said of PDS's.  Be wary of the time of day where things get really warm.  Travel fast through high risk terrain.  Plan transitions accordingly. 

author=freeskiguy link=topic=30926.msg129805#msg129805 date=1393692934">
Lowell, So the idea is to wait and see what us avy test dummies find and report? Then the op has saved some lives  and should be thanked for taking a big risk.   Thanks.


Maybe you missed my previous post:

I have to say ALL OF US have been very lucky to have this hazard demonstrated so vividly without anybody getting hurt. shawnskis should be thanked for bringing this discussion into the open by reporting his party's experience.


So, yes, I've thanked shawnskis for being willing to bring this discussion into the open. I'm not asking anybody to go risk their neck, but I'm going to watch any reports that do show up.

Did you see davep's post here? There's lots of evidence of deep instability out there that's independent of backcountry ski trip reports. Especially from the ski area avalanche patrols.

http://www.youtube.com/watch?v=dXXHOaZyXj8

http://kimkircher.com/2014/02/23/big-avalanche-results-and-more-about-treewell-safety/

Nobody's asking you or anybody else to go out into the backcountry when it's sketchy. People are doing it because they want to get the goods first. If you don't care about getting the goods first, you can be a lot safer.

JJ- for routes like that for me, maybe not the remainder of the season. This is particularly true of known big avy paths (and I've seen the deposit zone beneath that one when touring past from Snow Lake). But even true of other long consistently steep opens slopes. Would I go do Jim Hill in upcoming powder? Not so sure for this, let alone the big funneled slide paths. We'll see. If we get a big spring slab cycle on all aspects, maybe after that, on a day that has had a good overnight freeze (after multiple nights/days like this). If we get a ferocious pineapple event, depending on how new snow piles atop that, then I might modify my stance, but I can have plenty of fun on much more moderate lines for seasons to come so I'm in no rush. Maybe another season where despite the risk being non-zero, it appears to be much more confined to the very top layers, and we have something more in the low/moderate risk range for those layers. But I lean toward the conservative side anyway. I have been interested in getting onto that terrain, but have not had the snowpack, my schedule, and partners align for multiple seasons so I've not gone there yet. Just as I've been careful not to cultivate a taste for fine and expensive wine, I've avoided cultivating a taste for places like long steep deep couloirs. If I develop these tastes, I'm not sure I trust myself to make good calls all the time. I can still truly enjoy a $10-$20 bottle of wine, and I had a BLAST meadow skipping low angle slopes last weekend.

Learn how to fully enjoy all sorts of terrain and all types of skisport.  There are many ways to maintain adventure and/or physical challenge other than cruising steep terrain on what can be called high-risk days.

Skiers in this region routinely ski steep terrain as the snow is generally forgiving allowing perhaps, a skewed sense of what protocol is important when evaluating a day's objectives.  Again this could be the result of rarely proving the negative and that getting ingrained into TRs and intra-community discussions.  

Little of the steep terrain is new to skiers as skiers from half a century ago skied these runs.  What is different is, number of skiers on these runs as the sport grows, gear that makes these trips easier, and an implied imperative to get there first.  

Powder isn't popular because it's hard, it's popular because it's fun... and easier than say, thousands of vertical feet of breakable!  


Shawnskis

This was the best report ever on TAY.  It has been very interesting reading all these other takes on this and the variance of opinions.  I do not dis you or anyone who participated in this conversation.  I was skiing on that very day, rolling the dice.  My partner wanted to stop and I wanted to go higher on a slope we were skiing.  We chose his suggestion.  Later I was happy when a tree bomb triggered a slide on the more open portion of the slope.  It probably would not have buried us, but you could have been severely injured.  I thanked my partner for his wise choices, my problem is containing my pow fever and listening, he helps me do that.

This is all a massive game of probabilities and like gamblers or stock market players we all except various levels of risk tolerance.  Avalanches are only one factor there are other things like tree wells and steep icy slopes on which you roll the dice.  When we were out there were tree wells big enough to swallow a horse.  Here we do not risk money and instead risk injury or death.  Sadly to ski pow you have to sometimes take a few risks.

I do not think anyone was trying to blame NWAC in this discussion.  They are at best 40% of the equation, not even that.  What I thank them for is the wonderful amount of data they provide for us as to the conditions when we decide to roll the dice and their forecasts on the weather are usually more than 75% correct.  Those folks do a great job!

Oh I am certain there is a weak layer down there from the warm January weather and there will be big avalanches on that all the way through the spring maybe into early summer.  That warm January was a bad thing and following it with so much snow was not good either.  On KIRO TV they had a picture of a monster one they shot with a charge from a helicopter that probably rode down on that weak layer.  Everytime you go by one of those big open slopes above you thank the Avalanche Goddess for allowing you to go by.  Me not being an avalanche expert will never know for certain when and if one of those slopes will go.  I got some rudimentary ways for improving my odds, but it is again just a dice roll.

I will continue to refer to this site.  I know I have learned by this to be even more conservative at least for this year.  This was overall a bad ski year due to the rotten start.  I rate it in the bottom ten of my 50 years of skiing for various reasons.   I have gotten some decent powder days, but we do have our problems.  I will be out tomorrow once again rolling dice because Monday there comes another blowup (warm temps rising FLs)........thanks again for all this information and Thank you again Shawnsis for the best report I have ever read on this website.  Oh Shawnskis thank the Avalanche Goddess for only stealing your gear!!

jj-
Right now is probably one of the safest times to ski the north face of chair peak.  It slid.
I don't really have any criticism of the op. I can say the north face of chair was not on my list last weekend, but thats a choice I can only make for myself.
I'm puzzled by the choice of line, but let's not forget:
The group had considered their elevated area to transition for its protection from a slide from above, which it provided.
It seems the group did not trigger the slide. They considered the risk of something coming down from above, accepted it, and tried to minimize it. MN took a swing at them and missed.
Sounds to me like they took the risk of backcountry skiing seriously and weighed it against the benefit of a REALLY fun activity. They used their prior education and information to mitigate risk, took care of each other when something went wrong, and made it out safely. I'm sure they've all reconsidered their choices for the day, and will try to learn from the experience. That's right, they've gained experience. I hope they find their equipment, and continue to enjoy backcountry skiing with greater knowledge and experience. Thanks for sharing.

author=kneel turner link=topic=30926.msg129814#msg129814 date=1393700154]
Right now is probably one of the safest times to ski the north face of chair peak.  It slid.
I thought about this as an answer, modulo the potential hangfire that may remain on the edges of what slid. But It seemed more in the spirit (and wording) of the question to answer WRT to similar slopes that haven't yet slid.

I too have no criticism of the OP - only questions as to what their considerations were WRT wind loading above their line and the uncertainty level of the whole post-January load's stability. Neither of these are really apparent to me from the report, and for me this gets to the question of whether they were truly just somewhere far apart from me on the risk tolerance scale or not (which IMO is neither good nor bad as long as people aren't taking the risks in ways that clearly endanger others).

Great thread.  My thanks to the OP, Marcus for hosting the site and to all who have chimed in. 

I have little to offer other than I saw the largest crown I have ever come across (I remember thinking that it must have been 12') on that aspect of Chair in April a few years ago.  That stuck with me and I doubt that I would have put myself under that slope so soon following a significant snow event.

author=kneel turner link=topic=30926.msg129814#msg129814 date=1393700154]
The group had considered their elevated area to transition for its protection from a slide from above, which it provided.


I'm not sure that is a fair assessment Ed; all three of them were swept up despite their attempt to "run" away.  (The thought of running away from a slide in powder snow underscores how important evaluating the safety of a 'safe zone' can be.)

author=Floater link=topic=30926.msg129813#msg129813 date=1393699688]
This was overall a bad ski year due to the rotten start.  I rate it in the bottom ten of my 50 years of skiing for various reasons.   I have gotten some decent powder days, but we do have our problems.


I really do think it has a lot to do with how you look at it. I'd agree that overall, it has not been a very good year. We were first teased in October with a lot of surprising autumn snow, but not really enough to last until the true ski season started. Then we suffered through minimal snowfall and that warm January, followed by this 2-3 weeks of uberdump. Though despite that, January had some great corn skiing, and the dump provided lots of really fun mellow pow and storm skiing. Sure, I didn't get out and ride anything "exciting" but by making the best of it, got a whole bunch of good days. Skiing the mellow stuff can be a lot of fun, and it has the huge benefit of not having the back of your mind focusing on "what if..." There is something to be said for the removal of stress provided by taking it relatively safe.

On a tangent, I'm going to go out on a limb (and perhaps piss some people off) by putting forth the question: does the lure of boasting on the innerwebs push people into some risk they might not normally take? I think some people would (perhaps this is obvious) rather post a report about skiing something "cool", maybe pushing the limit a little bit and generating some interest and wow factor from that post. Something out of the ordinary, "bold" or scary is likely to generate more views than a post saying you skied absolutely amazing powder on mellow slopes in the trees and had a wonderful day. The same effect can be achieved on a smaller scale among a group of friends, but not on the same scale as taking it to the public and posting online. It is human nature, and I think it's at least worth some self reflection. I'd say it is one of the major reasons why while I enjoy engaging in these random discussions, I stopped posting trip reports years ago. I'm not saying this drives everyone, or is ever really the determining factor for many, but I do think it can be a background factor that drives some. Is showing off for a largely anonymous group online really worth any sort of risk? In the end, it might be worth asking, what exactly is the point of posting a TR in the first place? Does it really matter that people know you did something cool, or should it more be about the experience you had yourself and with your friends, and what you personally gained from it? I say all of this not out of criticism in any way (heck, I occasionally benefit from the conditions reports provided in TRs, as I'm sure others do), nor direct it at anybody, but as food for thought within the context of this larger discussion.

As for the rest of this season, I'd say I will be keeping it mellow and low-risk, probably in line with the decision a good number of us will be making. Spring will be here at some point, the real warm weather will arrive, the snowpack will finally get its complete baking and consolidation, the big healthy slide cycle and the Spring skiing season will start. Hopefully with all of this late season snow it will be a good, long one as well. Spring is a better time than Winter for going deep in to the mountains anyway. In the mean time, there will be more mellow powder, long days of excercise while exploring non-exposed approaches I've wanted to check out, lift skiing, and the like. Still lots of ways to have fun!

Joe, I get what you're saying. I think we can all agree the safe zone is on the couch. The safest choice at the time was to be on that bench. It worked.

author=freeskiguy link=topic=30926.msg129811#msg129811 date=1393698240]
Lowell,your last sentence is not accurate,care to re-think it?

author=Lowell_Skoog link=topic=30926.msg129807#msg129807 date=1393695636]If you don't care about getting the goods first, you can be a lot safer.




Sure, if we're not just playing word games.

I think I just restated Ian McCammon's "scarcity heuristic."

Here's a reference (see section 3.5):

http://www.snowpit.com/articles/traps%20reprint.pdf

Some excerpts:

Most skiers are familiar with the “powder fever” that seizes the public after a long-awaited snowstorm. Intent on getting first tracks down a favorite run, hordes of skiers flock to the lifts and the backcountry, often throwing caution to the wind as they compete with each other to consume the powder that is untracked for a limited time only.
...
In short, the presence of scarcity cues corresponds to an overall increase in avalanche hazard exposure among all groups. Further investigation will be needed to asses the exact influence of scarcity cues on groups of varying sizes and training levels.
...
Consistent with what we would expect, the scarcity heuristic appears to work exactly contrary to personal safety; it is most influential when the avalanche danger is high.


If you have a different perspective on this, I'd be eager to hear it.


Thanks OP. A great thread, with so many valuable comments on both sides.

Amazing that I could be so close at the exact same time (east side just above Source). Amazing that no one was killed as there were quite a few parties out that day. Now I am wondering if I saw your team, as while we did not head out until 830, we caught up to a bunch of parties.

I do remember seeing the aspect chart on NWAC highlighting the NE - N exposures as wind loaded and that actually made me think about the east side of Chair and whether it was safe. 

Perhaps IMHO the best part of this discussion is the PWL context, or not. As I thought more about last weekend, and remembered the quote from the Pro Bro that I rode up the chair with on Friday at Alpy ("I calculated this morning.....Sun - Thurs 96 inches of snow"), that it seemed to be more of a recent storm slab on top of a crappy crust, not a traditional PWL. That said, the conversation about the PNW skier not readily identifying that hazard is certainly true as well.

Everything else aside, just glad that 3 brothers are alive and will ski another day.

i still think that 2/3 got lucky that 1/3 didn't get them killed.
b

Several people have inquired about what professionals do in dealing with a PWL. First off here is an article about the character of persistent deep slabs that was linked by the NWAC: http://www.avalanche.ca/uploads/decisionmaking/DM_AvalProbEssentials_DP_V1.0.pdf

Put me in the camp that would have (and did) choose avalanche safe terrain on that weekend. I chose forested terrain and picked a destination where much of the trail breaking would be in the woods where it is easier. I would have made the same decision regardless of whether there was a persistent weak layer or not, just based on the amount of new snow in the preceding ten days. I made that decision knowing that if I made a mistake in evaluating stability and triggerred (or got caught by) a slide it could be injurious or fatal. A situation like this one is like playing with a loaded deck, one may only get one mistake.

I won't question the OP's choice of terrain. As the OP suggested, I will ask a question. The OP said that "while not completely ruling out the persistent slab". What was the Op's tolerance for risk before the incident?  And how has it changed after this lucky brush with death? I think a lot of backcountry skiers would have trouble defining in real terms their tolerance for risk and how they factor into it the possibility of severe injury or death. I can say that one avalanche accident I had made me completely re-evaluate my tolerance for risk and my methodology.

I will also ask the OP if he had been following the avalanche forecasts regularly (on a daily basis) prior to planning this trip. I would note that the persistent weak layer and failures in this layer were noted nearly daily from first snowfall that buried the weak layer through about Wednesday (Thursday's avalanche forecast) before the accident (3 days previous to the accident).

I don't respect the OP's criticism of NWAC and the avalanche forecasts. Telemetry shows that only about 6" of new snow fell on Thursday and Friday at Snoqualmie Pass and therein lies the reason the OP found good stability in surface new snow layers. However, near ridge lines sustained winds in the 20's from the West with gusts to 30 also occurred through Friday. So, the OP would probably have found still unstable wind slabs at higher elevations and near ridge lines. And any avalanches could have stepped down into still recent deeper buried weak layers. In fact if the OP's avalanche was triggered by a smaller avalanche or cornice off Chair Peak the wind probably played a roll (otherwise we have to assume the massive slab was human triggered (which seems unlikely).

Having asked two of NWAC's forecasters what Considerable means to them, it means that they would expect to hear of a few incidents. That would be across the range of their forecasting area. So, the Op's finding stable surface snow where the OP travelled is really meaningless in the bigger picture. In any case the OP probably observed a small avalanche or a cornice fall of unknown size on this particular day which triggered a larger avalanche. It is evident the OP's observation of stability in this one location can only be taken with a grain of salt.

author=jj link=topic=30926.msg129797#msg129797 date=1393663808]It seems we all agree that there's a persistent weak layer (or whatever you prefer to call it).  When will you be comfortable to ski routes like Chair (or similar terrain) given that knowledge?


The answer is "who knows?". We'll just have to see how it plays out. I certainly won't be pushing it for a while, but there is always plenty of safe, fun skiing to be had. Since you would like some specific answers, I am going to provide some very specific answers on why specific answers are temporarily unavailable.

* The issue with persistent weak layers, and the reason that many people consider them to be unmanageable is because a persistent weak layer is an enormous engine of uncertainty relative to numerous factors that are very important for backcountry avalanche forecasting, as well as for aspects of the backcountry avalanche forecasting process itself. This is important because our perception of instability is always worst when uncertainty is highest.

- There is often a fairly basic uncertainty about the distribution of a weakness by elevation and aspect.
- The duration of the drought, cold temperatures, and diurnal radiation create uncertainty about the morphology of weak crystals.
- Are the characteristics of the weakness similar in most places? Different in most places? Different in a few important places?
- Variations in local precipitation increase uncertainty about the depth of the weak layer from the surface.
- Variations in depth from surface increase uncertainty about positive and negative changes to crystal form and interface parameters as metamorphism continues.
- That is, the weakness can become worse in areas where the overlying snowpack is less than a metre deep.
- Weakness can decrease in areas where the overlying snowpack is deeper than 1 metre.
- Local variations in weakness vs. strength create additional uncertainty that readily propagates across various spatial scales.
- On top of all this uncertainty is the normal uncertainty relative to temperature, recent load, aspect, elevation, and so forth.

Avalanche forecasting shares many characteristics with Bayesian probabilities ( prior, likelihood, posterior ) in that most predictions about current snowpack instability rely on having solid distributional information ( the winter history ) and high-quality singular information ( the current situation ).

The uncertainty inherent in persistent weak layers makes it incredibly difficult to establish both distributional and singular information, which means predictions are more akin to gambling than anything else. The uncertainty affects the information that serves as inputs to the process of backcountry avalanche forecasting, and the uncertainty affects the process of backcountry avalanche forecasting as well. I guess one could say that the uncertainty inherent to a PWL is a double whammy: not only is it harder to collect information, but the uncertainty makes it much more likely that you'll blow the prediction. These rules apply equally to EVERYONE regardless of experience, education, knowledge, hair colour, time of day, or risk acceptance level. That's why:

* Best practise dictates that decision characteristics take on an increasingly conservative flavour as uncertainty increases. Full Stop.

author=jj link=topic=30926.msg129797#msg129797 date=1393663808]In my mind you don't get to armchair quarterback someone else's decision if you aren't willing to commit to your own decision.


Your remark is patently fallacious.

A very significant amount of acquired human knowledge involves, and has arisen from, the search for, development of, and comparison of practises, both in a particular domain and across domains.

I don't what a guide or guides say are definitive by any means or the NWAC --there info is only a small part of my decision making of which I am ultimately responsible for...there are NO EXPERTS only people that know more than me (possibly..).  Just because everybody else (who is an "expert" ) is doing something does not tell me it is safe, no matter how long they have been doing it.

If you see no sign of activity, and there are all sorts of indicators of potential danger such as a very steep slope that could be loaded (what are the indicators?)-- the steepest of slopes are obviously more prone to sliding than the lower angle ones (angle of repose...have not heard that nomenclature for years but nonetheless still applies). 

Thanks for the write-up and glad you are ok--you are not alone, I too have learned the hard way.

Rebob on Earn Your Turns discusses deep persistent weak layer:

Having said that, although the local bulletin for Whistler/Blackcomb is L/L/L it clearly notes that there is a deep persistent weak layer that has not been reacting lately but could be reactive in some isolated areas. My take on that would be that I would want to avoid the areas most likely to see that layer activated--for the moment, big, unsupported steep slopes would be completely off my list even thought the rating at all elevations is Low. A regular question is always how one will manage terrain. While the current rating locally is Low, that doesn't mean that experienced people would necessarily treat all terrain as if it were "Low" avalanche danger.



I concur.

author=rlsg
Thanks for the write-up and glad you are ok--you are not alone, I too have learned the hard way.

lucky they get another chance to keep learning, even the hard way.
b

I too have felt the hot breath of the Chair dragon
Take it to heart
Live

Up in Whistler and noting a recent forecaster blog. Should be a great inbounds powder day tomorrow. Today there was still some breakable crust to contend with off the groomed.


Some decisions are easy. Like the choice I made this morning to have a second cup of coffee after my toddler kept me awake for half the night. Also easy was the decision I made not to wear my florescent purple jacket I still have from the early 90′s and the decision I made not to click on the link to a video of Justin Beiber being patted down in a US jail by a burly looking policeman.

On the other hand, some decisions are hard. Here’s one: where to go riding to maximize the thrill but still come back alive so you can brag about what you did to your friends at the bar. Actually, sometimes, that’s an easy one. During low avalanche hazard where you can confidently push into steep terrain, for example. During high danger, when you’re best sticking to the flats. But it’s not an easy one right now. Let me explain.

High Consequence Snowpack

We have a high-consequence snowpack right now. If you trigger an avalanche, there’s a good chance it will go big. A size 3 avalanche is big enough to destroy a car and a size 4 can pull out a 4 hectare swath of forest.

Over the last 12-14 days, a weak layer dubbed “the drought layer” has caused all kinds of problems. There have been numerous reports of large, unusual, and surprising avalanches. Some of these were remotely triggered from as far as 500 m away from where the avalanche actually ran. We had reports of avalanches running in areas with sparse trees, in small below-treeline cut blocks, and on relatively low-angled terrain. There were numerous highway closures due to avalanche activity. And tragically, three people died in avalanche incidents in Canada*.

However, in the last couple of days as I write this, the nature of the avalanche activity has started to change. We’re seeing a reduction in the number of unusual and surprising avalanches. Don’t get me wrong, avalanches are still running, both naturally (particularly on slopes that are getting hit by the sun) and human triggered (from steeper terrain and on unsupported rolls where the surface hoar was well preserved). We are also still seeing those that do run go quite large because the weak layer is deeply buried. However, we’re not getting the same kind of reports of low-angled avalanches, dramatic remote avalanches, and the super-touchiness that was characteristic of the situation this time last week.

So what we can say is, while the consequence of triggering an avalanche is still high, the likelihood of triggering one has dropped.

Since avalanche danger is a combination of the likelihood of triggering and the consequences (i.e. the size) of an avalanche, we are seeing danger ratings in many regions move into the Considerable and maybe even the Moderate range. We know from experience that when this happens many people become tempted to push out into aggressive terrain. Here’s the sixty four thousand dollar question: has the likelihood of triggering dropped enough for this to be a good decision?

Personally I don’t think so. And I’d venture most professionals would agree with me.

I suspect all of this "atmospheric river" precip this week will take care of a lot of the PWL areas and might hit the reset button for most of the snowpack where I ski, Stevens to Crystal.  Of course it might still be there, especially up higher, but it will certainly help alleviate my fears.  PWL in Colorado don't get this kind of soaker now do they hence why they stick around for a long time during the season?

author=haggis link=topic=30926.msg129903#msg129903 date=1393869651]
I suspect all of this "atmospheric river" precip this week will take care of a lot of the PWL areas and might hit the reset button for most of the snowpack where I ski, Stevens to Crystal.  Of course it might still be there, especially up higher, but it will certainly help alleviate my fears.  PWL in Colorado don't get this kind of soaker now do they hence why they stick around for a long time during the season?


Most of the reason PWL's last so long in the continental snowpack is: lack of snow, combined with cold dry weather creating a large temperature gradient in the snowpack. Meaning the air temp is much colder than the ground temp. The temperature gradient, mixed with a shallow snowpack is what preserves or even grows facets.

In a coastal snowpack like we have these layers typically don't last to long, with our warm temperatures, rain, and typically robust snowpack, although this year is a bit different.

I agree that with the warm temps, a new bridging crust layer, and the amount of new snow on to, that if the buried weak layer doesn't heal, or fail from loading, I think it will be very hard to trigger by skiing.

I've thought of going up safe routes that lead to the tops of avy terrain and dropping some big cornices, and see where we stand.

author=powhound link=topic=30926.msg129909#msg129909 date=1393874872]
I've thought of going up safe routes that lead to the tops of avy terrain and dropping some big cornices, and see where we stand.


If you end up doing this, please record video in case you get something to go, and then share it. :)

.....and were back to flaunting high risk maneuvers for interwebz adulations, hope that anyone below the cornice is as lucky as the op's party was.
b

author=flowing alpy link=topic=30926.msg129918#msg129918 date=1393882352]
.....and were back to flaunting high risk maneuvers for interwebz adulations, hope that anyone below the cornice is as lucky as the op's party was.
b


Sorry, I forgot sarcasm doesn't translate well over text. I guess I should have stayed with my original comment recommending that he "look for a cornice over a frequently traveled trail." :P

Though FWIW, dropping cornices on slopes is sometimes practiced as ghetto avy control. I would hope anybody doing this would verify the absence of anyone in harm's way. I'm not saying I endorse this, but it is done, and in fact products are sold for this particular purpose. (lawsuit inc? :P)

author=haggis link=topic=30926.msg129903#msg129903 date=1393869651]
I suspect all of this "atmospheric river" precip this week will take care of a lot of the PWL areas and might hit the reset button for most of the snowpack where I ski, Stevens to Crystal.  Of course it might still be there, especially up higher, but it will certainly help alleviate my fears.  PWL in Colorado don't get this kind of soaker now do they hence why they stick around for a long time during the season?


It will be interesting to see what happens this week. 

author=garyabrill link=topic=30926.msg129839#msg129839 date=1393721611]
I will also ask the OP if he had been following the avalanche forecasts regularly (on a daily basis) prior to planning this trip. I would note that the persistent weak layer and failures in this layer were noted nearly daily from first snowfall that buried the weak layer through about Wednesday (Thursday's avalanche forecast) before the accident (3 days previous to the accident).

I don't respect the OP's criticism of NWAC and the avalanche forecasts. Telemetry shows that only about 6" of new snow fell on Thursday and Friday at Snoqualmie Pass and therein lies the reason the OP found good stability in surface new snow layers. However, near ridge lines sustained winds in the 20's from the West with gusts to 30 also occurred through Friday. So, the OP would probably have found still unstable wind slabs at higher elevations and near ridge lines. And any avalanches could have stepped down into still recent deeper buried weak layers. In fact if the OP's avalanche was triggered by a smaller avalanche or cornice off Chair Peak the wind probably played a roll (otherwise we have to assume the massive slab was human triggered (which seems unlikely).



Well Said

It would be interesting to fly around the Cascades (were there visibility) and see just how many and how big of slides will go between Tuesday afternoon and Thursday PM. Baker has already had 46" of new snow since Saturday and snow levels are going to 6000-7000' for the first time. I would suspect this layer will be unheard from after this cycle until about the second week of May when prolonged warm temperatures will again reawaken the monster in isolated locations.

To be honest, I am a little confused by the OP's critique of NWAC. Is the claim that they were warning of too high a risk? Of too low a risk? It seems both. Granted, it is parsed between human and natural triggered, but, on the assumption that this was naturally triggered from something happening above, in the wind loading by the ridge, isn't it a fair guess that a human would have triggered a similar slide if they ventured onto the starting zone? And doesn't the "considerable" rating by definition warn of a possibility of natural slides? The Friday afternoon discussion warned of uncertainty about the deeper snow layers as well.

So I'm left a bit puzzled by the NWAC part of the OP. And left with questions such as - was the slope above the supposed "safe zone" wind loaded at any point? Were there any overhanging cornices, which given the ongoing snow movement that I noted a few miles away at mid-day on the 22nd, could have been quite fresh and unstable, and thus creating more of a risk of naturals? I don't know from the info in the report, but it seems like a reasonable guess. If the OP isn't sure or doesn't want to comment at this point, perhaps others who are familiar with that terrain might hazard a guess, given that the winds had been fairly typical in the days and hours leading up to the incident.

It would have taken an awful lot of paid observers (pro, not merely commercial) to more precisely pin down the hazard on this specific slope; and would double the number of paid observers have significantly reduced the uncertainty level about the deeper layers??

author=garyabrill link=topic=30926.msg129943#msg129943 date=1393904980]I would suspect this layer will be unheard from after this cycle until about the second week of May when prolonged warm temperatures will again reawaken the monster in isolated locations.


Queue HWY 20 washouts.

author=RonL link=topic=30926.msg129511#msg129511 date=1393432472]
Thanks for stepping up when you know there will be some criticism. I don't have any criticism for what you guys did. I can only say the reasons that I chose different terrain that day and similar ones. After a few years of this sport many of us have begun to focus on what we don't know about the risks and to find ways to mitigate it more rather than to find the true barriers of what is safe or not. One rule of thumb I have fallen back to is to ski lower angled older treed terrain following a storm like this until I have more assurance that a layer like that is stable. That assurance wasn't there for me with this storm because the only dramatic change throughout the storm cycle was that more and more new snow continued to pile on top. The nwac rating, people's pits, trip reports etc. we're irrelevant too me until I saw some sort of warming or soaking event that would thoroughly test the bond on that layer. I likely would have kept to less open slopes until such an event occurred and even afterward I would have had some concern about that layer until after the first large warmup in the spring. I am not an expert and unfortunately I have not always been smart enuf to take my own advice but for what it is worth that is why I chose to stay away from terrain like chair and even the slot. I would not have posted on a trip report about chair or the slot on days with similar risks simply because I am not an expert and couldn't tell those people whether or not they made a decision that was unsafe. It is that that inability to know whether it is unsafe however that kept me in more protected terrain. Thanks again for sharing and I am glad you all came out ok. You are in good company with people who have made mistakes.


+1 This echoes my sentiments.

Also, everyone has different risk profiles - there's not one size that fits all category here. The only way to live is not go and there's no fun in that. I try to mitigate risks in every aspect of my life and the BC ranks pretty high up there...two young boys and a pretty wife will do that.  Safe to all and thanks for sharing.

I'm way late to this thread, but it will never be old.

I've done that route and it's in a zone with no trees, lots of rollers up top, then a big wide chute. I personally wouldn't have gone near terrain like that until 2 to 3 days after the storm. The lack of snow for a long period then massive amounts of snow is a huge red flag. In avalanche training we're trained to consider the entire season of snow and the constant changing of the make-up, not just how observations a day or two before, and certainly we were not trained to rely on NWAC reports (appreciated though...).

Glad everyone's okay.

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