Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
December 31, 2022
Submitted:
December 31, 2022
Observer:
NWAC Forecaster - Matt Primomo
Zone or Region:
Stevens Pass
Location:
Mt McCausland

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
None Experienced

Media/Attachments

Boulder gardens filling in.
Isolated cracking while setting a skin track revelead a density change, likely the new/old interface.
Small natural loose slide, probably from a tree bomb.
Settlement cracking around a tree.
Wind effect at 5,200ft

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Wind:
Light
New/Recent Snowfall:
Found an average of ~80cm over the Xmas crust, 40cm over a noticeable grain/density change.

The day felt stormy at times, but generally quite mild and damp. Some snow transport observed at the top of Lichtenberg and ridge of McCausland.

Observed a few small (D1) soft slabs that likely ran yesterday during the warm-up and heavier snowfall on a variety of aspects and elevations BTL and NTL. These were all about 30cm deep, with 5cm or so of newer snow on top.
One small loose slide that was likely triggered by a tree bomb- NE at 5,600ft (see photo).

Snowpack Observations

Ski pen was boot deep, and felt somewhat upside-down with slow travel. A very soft, weaker snow layer beneath the recent storm snow was consistently failing with hand shears as we traveled. We observed isolated cracking as we broke trail as well. This layer was 30-40cm down on average, and was a noticeable density change with a pole probe, especially earlier in the day.

A profile on NE aspect at 5,500ft showed an HS of 275cm. 80cm down to the Xmas crust. CTE SP down 40cm, and ECTP M x2 down 40cm.
Moist snow was found on top of the Xmas crust, which was quite different at this elevation than the impenetrable ice lens down at 4,000ft. Here, it was more of an opaque crust with refrozen grains. No results here, and snow above seemed very well bonded at this elevation.

Some thicker wind affected snow was 4f+, but didn't react on a few mediocre test slopes. We skiied fairly conservatively with the obvious weakness, and deep snow at play.

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