Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
March 23, 2022
Submitted:
March 23, 2022
Observer:
NWAC Forecaster - Josh Hirshberg, Irene Henninger
Zone or Region:
Stevens Pass
Location:
Cowboy Ridge and Big Chief Mtn (4,000-5,780ft, all aspects)

Signs of Unstable Snow

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

Media/Attachments

Numerous wet loose avalanches occurred in the west fork above Lake Susan Jane on March 21st. NE-N, 4800-5,600ft.
Wind features on the southwest face sof Lichtenberg Mtn.
Looking to the east, low fog hangs in the Icicle Drainage, near the Cascade Crest.
Numerous wet loose avalanches occurred in the west fork of the Tunnel Creek drainage on March 21st. E-N aspects.
Profile from Big Chief Mtn. The March 8th facets, about 45cm below the surface, were barely perceptable, very rounded, and moist. 5600ft, NW.
another view of the profile on Big Chief Mtn, NW, 5480ft
Profile from Big Chief Mtn, NNW, 56,00ft. 3/8 facets were poorly formed and produced variable test results.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Cloudy
Temperature:
38°F
Wind:
Light , W

Thick valley fog up to 5,500ft in the AM, yielded to broken skies w occasional lingering low clouds. Infrequent moderate gusts.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
12 Mar 21, 2022
() 		Big Chiwaukum
SW 6600ft 		D2 WL-Wet Loose S-New Snow N-Natural Report
10 Mar 21, 2022
() 		Tunnel Creek, West Fork
NE 5800ft 		D1.5 WL-Wet Loose S-New Snow N-Natural
Numerous wet loose avalanches occurred in the west fork of the Tunnel Creek drainage on March 21st. E-N aspects.
Report
7 Mar 21, 2022
() 		Lake Susan Jane
E 5600ft 		D2 WL-Wet Loose S-New Snow N-Natural
Numerous wet loose avalanches occurred in the west fork above Lake Susan Jane on March 21st. NE-N, 4800-5,600ft.
Report
Big Chiwaukum
Tunnel Creek, West Fork
Lake Susan Jane

Decent visibility allowed us to see the widespread wet loose cycle from 3/21 on all aspects and elevations. Most were D1-1.5, with some D2s. A few slides seemed to be from 3/22. Some older roller balls were 5ft in diameter.

Snowpack Observations

Surfaces were moist to wet and weak. Much of the upper snowpack is moist up to 5,800ft on all aspects. Only select layers have transformed to large melt form grains. Near treeline, rain from 3/21 seemed to mainly affect the top 10cm.

At a profile site on Cowboy Ridge, 5,350ft, SSE- March 8th facets not present
0-31cm F hard 3/20-21 storm snow
31-33cm 1F hard
33-34cm 1F hard, melt forms
34-35cm 1F- hard
35-37cm P hard, early March crust
37-83cm 4F-1F hard

Another profile on Big Chief Mtn, 5,600ft, NW
HS 280cm
↓46cm 4F+, melt forms and facets, facets: 0.5mm, very rounded, 3/8 layer
Tests: ↓46cm CTM(SC), CTH(RP), ECTX
See profile images for more details

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wet Loose
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Comments: Avalanches were easy to trigger on open slopes 40deg and steeper.
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