Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
February 10, 2022
Submitted:
February 11, 2022
Observer:
NWAC Forecaster - Matt Primomo
Zone or Region:
Stevens Pass
Location:
SPMR- Big Chief area

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

Melt freeze conditions on ridgelines, and exposed rock.
View to the west of the pass with some scattered low fog.
Large WL slide with more recent smaller ones to the right on SE aspect of Lichtenberg.
Sheen of surface crusts even on high N facing terrain. Nimbus Peak.
Small WL slides on SW facing terrain west of Stevens Pass

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Wind:
Moderate , NW

Warm and breezy. No snow for transport.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
1 Feb 9, 2022
() 		Lichtenberg
SE 5400ft 		D2 WL-Wet Loose N-Natural
Large WL slide with more recent smaller ones to the right on SE aspect of Lichtenberg.
Report
3 Feb 9, 2022
() 		Lichtenberg
SW 5200ft 		D1 WL-Wet Loose N-Natural
Small WL slides on SW facing terrain west of Stevens Pass
Report
Lichtenberg
Lichtenberg

Observed a couple WL avalanches off SW facing terrain west of Skyline Ridge (D1), and a few WL avalanches off steep SE facing terrain on Lichtenberg (D1-2).

Snowpack Observations

All aspects have a surface crust, as evidenced by the sheen on higher northerly facing terrain from afar and direct obs. Slopes in the sun were manky and any surface crust was mostly melted down and gone by mid-morning. These E-S aspects held dry/moist snow underneath the upper few inches of wet snow on the surface, and very large rollerballs could be easily triggered. I didn't travel in steep enough terrain to really test wet loose avalanches, and left the field before the heat of the day. I did get one started but it hit some lower angled slopes that prevented it from running. With a sustained, very steep slope it appeared slides could run and pack a punch.

I dug a profile on a 20 deg ENE aspect at 5,620ft to check on the late January PWL.
HS was 320cm
CTX, DTH RP down 45cm on 1/30 (0.5-1.0mm FCxr)
PST 43/100 (End) down 45cm. Note Propagation was sluggish and at first it appeared the column had arrested.

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