Home > Trip Reports > December 18, 2014, Crystal Silver Basin

December 18, 2014, Crystal Silver Basin

12/18/14
WA Cascades West Slopes South (Mt Rainier)
24617
5
Posted by r1de on 12/19/14 5:33am
We had originally been looking at Paradise, but due to weather concerns and good intel from a Crystal local that the high country was in good shape, we diverted to Crystal instead in hopes of an earlier start, shorter drive, and a change of scenery.

Our party of 4 was three splits + 1 AT.

We got an 08:00 start from the base, where it was lightly snowing and a scant few inches on the ground - just enough to skin from the bottom of Discovery.  Surveying the hills led to many doubts about what kind of coverage we'd find, but by the time we reached the start of the usual Silver Basin uphill track, coverage was looking encouraging.

We found a safe and easy track leading through the creeks, around the lake, and up the drainage to the bottom of Silver Basin.  The weather had been lightly snowing with fair vis and virtually no winds.  Coverage had increased and surface snow quality was light, so we were feeling pretty optimistic about finding good turns ahead.

We had been eyeing turns off the Box Car and some very enticing chutes off of Three Way, but decided to dig two test pits first.  Pit location was 46.91, -121.4985 (low shoulder of west side of Three Way) on a NNE aspect slope of 34° at about 6400', 11:15.  Total snow depth was between 70cm and 90cm depending on the location.  There was a moderate fracture of a very thin layer of storm snow on top (75cm), with no propagation.  More interesting was a pencil hard rain crust layer at 50cm, at which we could get to Q2 shear at several arm taps.  Although some yellow flags were raised, we felt that propagation was not occurring and the snow above this layer was not consolidated.  Also note that we observed no natural slide activity or red flags anywhere.

Nonetheless, we opted to start the day with a mellower descent down the Box Car and reassess.  We followed a murderous preexisting skintrack that transitioned to bootpack near the top of the Box Car, where we found significant SW winds.  We descended to the NE one at a time and found nonreactive, light, unconsolidated powder snow accompanied by high-5s and hell-yeahs.

After that, we kicked in a bootpack up one of the chutes we had been eyeing on the west shoulder of Three Way.  The bootpack was very solid and the snow was right-side up!  Again, once cresting the ridge we were blasted with significant winds from the SW, though there was no wind slab formation in the chute, which skied really nicely.  Again, we single filed this one.

At about the same time we were climbing the chute, we saw another party ascending up Box Car.

By 14:00 we called it a day: visibility was decreasing and temps were warming.  We returned to the base under a 36F light rain.

The crowds were light: we saw only one other group of tourers in the same area, plus a few solos (including 1 shoer).  There was another group we talked to back at the base area that reported going out North and into Green Valley.

SPOT track: http://share.findmespot.com/shared/faces/viewspots.jsp?glId=0F7DaFhlccyiNYn54kFMz7EUbmnYaq3Ho

Very similar experience for us today. We dug a hasty pit about 100 feet above where the person in your first photo was. Found the rain crust at 50cm. Decided not to ride the chutes (including the two to the right of the one you pictured). Another group, a young teenage snowboarder and skier were heading for the ridge and had talked about riding the chutes. We recommended a different route of descent, but they continued on. On our next lap from the main silver basin saddle, we observed slide debris coming from BOTH of those mini chutes. Talking to the young boarder and skier both of them had set off small slides on their first turn into the each chute. The skier was partially caught and carried a short distance but was able to stop quickly. They were a bit shaken.

sneaky_steve: thank you very much for posting that followup and especially for the report on the slides.  Do you have any more details about it?  Dry slough, or storm/wind slab from last night's new?  What was the total snow depth?  I'd like to confirm (or prove wrong!) my suspicion that the instabilities you saw were new storm snow and not a 40+cm slab releasing on that rain crust.  I'm also curious to know if you could see our tracks/bootpack into the eastern chute, or if it had filled in already.

Mike Cheney: John was in our party, but I (Bryan) wrote the TR.  John and I each put in a hasty pit and confirmed each other's results.

author=r1de link=topic=33099.msg137681#msg137681 date=1419056326]
sneaky_steve: thank you very much for posting that followup and especially for the report on the slides.  Do you have any more details about it?  Dry slough, or storm/wind slab from last night's new?  What was the total snow depth?  I'd like to confirm (or prove wrong!) my suspicion that the instabilities you saw were new storm snow and not a 40+cm slab releasing on that rain crust.  I'm also curious to know if you could see our tracks/bootpack into the eastern chute, or if it had filled in already.

Mike Cheney: John was in our party, but I (Bryan) wrote the TR.  John and I each put in a hasty pit and confirmed each other's results.


After I wrote my reply I was already thinking I didn't give enough detail.

We did not see any tracks leading up the chute. Our hasty pit showed about a 50cm slab on top of the rain crust. Our ECT results produced an ECT22 with gross/jaged (not clean) propagation across the column. Definitely a Q2-3. After that result we pulled the column off of the rain crust and examined the snow crystals. I don't know a specific name or label for the type of crystals we looked at, but they appeared more like a normal snowflake, rather than facets, hoar, etc. We speculated that the rain crust and snow layers above have likely been strengthening with the weather pattern in the last week. 

The slide results we saw in the two chutes skiers left of the main chute were very small storm slab releases at the top of each chute (the chutes are about 10-15 feet wide and only 100 feet long before opening into the bowl) that released into the bowls below and ran more like a simple point release. Likely storm snow and wind deposit buildup. Although we didn't observe it, the skier we talked to did say that he was "caught" in moving snow and had to fight to stop. We did not closely observe the top of the chutes to see if there was a crown of any depth.

author=sneaky_steve link=topic=33099.msg137683#msg137683 date=1419095566]
After I wrote my reply I was already thinking I didn't give enough detail.

We did not see any tracks leading up the chute. Our hasty pit showed about a 50cm slab on top of the rain crust. Our ECT results produced an ECT22 with gross/jaged (not clean) propagation across the column. Definitely a Q2-3. After that result we pulled the column off of the rain crust and examined the snow crystals. I don't know a specific name or label for the type of crystals we looked at, but they appeared more like a normal snowflake, rather than facets, hoar, etc. We speculated that the rain crust and snow layers above have likely been strengthening with the weather pattern in the last week. 

The slide results we saw in the two chutes skiers left of the main chute were very small storm slab releases at the top of each chute (the chutes are about 10-15 feet wide and only 100 feet long before opening into the bowl) that released into the bowls below and ran more like a simple point release. Likely storm snow and wind deposit buildup. Although we didn't observe it, the skier we talked to did say that he was "caught" in moving snow and had to fight to stop. We did not closely observe the top of the chutes to see if there was a crown of any depth.


Awesome info, thanks for the followup.  That gives me a little more confidence in our decision-making process: it sounds like what ran was new (between 10cm & 20cm) from the storm blowing in the afternoon as we were checking out, and through the evening.

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december-18-2014-crystal-silver-basin
r1de
2014-12-19 13:33:53