Home > Trip Reports > February 1, 2014, Mt Catherine North Slopes

February 1, 2014, Mt Catherine North Slopes

2/1/14
WA Snoqualmie Pass
4573
8
Posted by John Morrow on 2/1/14 12:04pm
We thought we'd have a cautious look today and were surprised at what we found.  Approached from the Nordic Trails and the blue diamond route to Nordic Pass.  Well below Nordic Pass we began our traverse to the north slope and started climbing in oldgrowth forest.  Avoiding some bony and tight patches threw me off a bit, and I struggled to find the route between cliff faces that gets you to the upper old growth slopes!  It all looked different with just enough snowdepth to get by on.  Many small trees showing in the forest that often are deeply buried.

What we found in the snowpack:
We remainded beneath oldgrowth forest canopy for the entire tour with the exception of the near mandatory small openings one must pass through to maintain a reasonable skin track.  Honestly, we found no buried surface hoar at the interface of the Tuesday storm snow and the January mega crust.  What we did find was roughly like this, surface downward, for most of the climb between 3800 and 5000 ft:
Note: these were brief tug tests after quickly isolating columns with poles and hands.  No quantative tests conducted.
10 to 20cm Fist hardness, fine uncohesive metamorphosed powder on the surface. Must have been a relatively cold night.  On top of:
10 to 15 cm, 4-Finger hardness denser powder, even damp below 4000ft.  No clean planar shears between the 2 storm snow layers.  We called it Q2.  On top of and generally bonded to: 
1 to 2 cm rain/freezing rain crust, Pencil hard.  We took out the lens here but could not find significant faceted snow on either side of this rain crust.  On slopes with angle the crust was supportive.  On top of:
10 cm, 4-finger older powder, mostly small fragments, not quite facets.  On top of:
Impenetrable January mega crust.  Again, not much sign of facets on the surface of the crust.
Lack of faceting probably due to the forest canopy, but held true even in small openings.

Direct observations: 
No woomphing when on any slope angle, though reported in flats by others, probable collapse of the intermediary rain crust.
Intermediary rain crust began to disappear just below the 5000 ft summit.
Could not get planar shears on switchbacks when jumping or tugging.
No shooting cracks.
No wind effect or visible transport in the protected forested slopes.
Trees held the snow all day. Some minor tree bombs on the snow surface, from wind in the canopy, I am guessing, some time prior to our arrival.
Skin track penetration less than 20 cm on average.
Surface and near surface snow remained light and uncohesive at all our altitudes for the enitre day.

If the party we met today has anything to add or correct, by all means, help me out.

It skied very well to 3600 feet.  On the actual north slope of Catherine itself, with effort to avoid the small tree tops, blowdown across the fall line, and marginally filled in watercourses.  My first day out since the 15 turns we got below Hidden Lake Peak back in October!  It was a real good one with Jake.  Hopefully start of many.

Nothing I noted above, in today's forested route, would convince me to venture out on any big open slopes tomorrow.  Certainly not near Stevens along Route 2 corridor!  I will be curious to hear from others if the buried surface hoar is less of an issue in the Snoqualmie region, if anyone does some tests on open slopes, or was it just because we stayed in the trees. 
Looks good! Lots of tracks?

Looking to go out tomorrow...recommend?

The canopy of the old growth trees can work to block the back radiation (trap the heat in), and prevent surface hoar growth underneath heavily canopied forest.

I skied a few different aspects at yodelin today without finding the hoar layer underneath the same sort of trees, it was also not present near ridge tops (wind kills it), but was present in open areas without overhead branches and protected from wind by surrounding trees.

Nice report.


author=camp_fidalgo link=topic=30606.msg128053#msg128053 date=1391314286]
Looks good! Lots of tracks?

Looking to go out tomorrow...recommend?


We met at least six other folks but aren't sure how they descended.  The snow seems good enough that some tracked-outness won't ruin the day.  It is very beautiful right now and should remain cold for a tour tomorrow.  on a north aspect at least.  Play it safe!

author=kerwinl link=topic=30606.msg128054#msg128054 date=1391315644]
The canopy of the old growth trees can work to block the back radiation (trap the heat in), and prevent surface hoar growth underneath heavily canopied forest.

I skied a few different aspects at yodelin today without finding the hoar layer underneath the same sort of trees, it was also not present near ridge tops (wind kills it), but was present in open areas without overhead branches and protected from wind by surrounding trees.

Nice report.




Thanks for the Yodelin update, and for taking a look at the snowpack out in the open. 

Thanks for the report. Should be good tomorrow!

Similar observations around Kendall Lakes today, both in big trees and in somewhat open-is areas. We could use another 4 feet of snow, but it was still pretty fun up there, despite the treetop and deadfall and creek rut dodging (and snowshoer shenanigans on the road back down).

Nice chatting with you guys on the summit on Saturday. What a great day to be out!

Thanks to all for sharing: Your interpretations of the Surface Hoar (SH) formation is exactly right. SH typically does not form underneath forest canopies due to the heat radiated from the surrounding trees and the inability for the needed microclimate to develop near the snow surface. I'm not at all surprise that you didn't see it in the tall timber. However at Radio Peak near Mt Catherine (last Thursday) and Yodeling (Friday) I experiences wide spread WHUMPING in open areas below treeline. It was so consistent and predictable that we were able to video it. Check out the video from Snoqualmie Pass on NWAC's YouTube channel. Remember that this SH may persist in isolated areas this week.


author=dallasglass link=topic=30606.msg128096#msg128096 date=1391454742]
Thanks to all for sharing: Your interpretations of the Surface Hoar (SH) formation is exactly right. SH typically does not form underneath forest canopies due to the heat radiated from the surrounding trees and the inability for the needed microclimate to develop near the snow surface. I'm not at all surprise that you didn't see it in the tall timber. However at Radio Peak near Mt Catherine (last Thursday) and Yodeling (Friday) I experiences wide spread WHUMPING in open areas below treeline. It was so consistent and predictable that we were able to video it. Check out the video from Snoqualmie Pass on NWAC's YouTube channel. Remember that this SH may persist in isolated areas this week.




Thanks for writing Dallas.  I am just getting back from Radio Mtn and Ski Acres Hill and have a thought to throw by you.  I could not get that crust to collapse on small open slopes (east facing), I never felt or heard woomphing.  The storm snow above that intermediary crust (up to 30cm in open, far less in forest) has seen significant settlement in a rightside-up density profile.  I even crossed Surveyors and Divide Lakes to see if the crust would collapse.  Here's my thought: is it possible the settling of the storm snow is aiding the intermediary crust in effectively bridging the low density snow beneath it and thus the surface hoar sitting on the mega crust? 
In the forest, to my surprise, the settlement and recycling of the surface powder (less than 20cm under canopy now) caused me to scrape the crust on descents when we floated above it on Saturday.

Despite my bridging theory, I still stayed off open slopes.  I never dug, just felt around with ski pole tests and reaching my hand into the pole holes.  i couldn't tell what might be happening to the sandwiched snow  between the crusts.  Felt like fine powder more than sugary facets.  This was out on the lakes.  Wasn't very concerned with the snow in the trees.
I'll try to do a TR later.
Thanks,
John

Reply to this TR

11606
february-1-2014-mt-catherine-north-slopes
John Morrow
2014-02-01 20:04:38