Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
February 8, 2020
Submitted:
February 8, 2020
Observer:
SAC - Savage (OFF DUTY - recreational trip)
Zone or Region:
Sawtooth and Western Smoky Mtns
Location:
Frenchman/Smiley Ck area: 7200-9500', mostly W-NW-N-NE

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
Isolated
Collapsing? 
None Experienced
Very minor cracking when kicking cornice chunks above 9200'.

Snow Stability

Stability Rating: 
Good
Confidence in Rating: 
High
Stability Trend: 

Bottom Line

We did not see any sizable avalanches, and we had enough visibility to see a decent amount of terrain when we were at upper elevations. The wind had loaded some slopes immediately below ridgelines (and built cornices) above about 9200'. The wind affects were confined to the ridgelines where we traveled. Snowmobilers were getting into some steeper terrain in the Frenchman Ck drainage without triggering anything.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Cloudy
Temperature:
teens F
Wind:
Light , W

Mixed bag of partly cloudy to socked in and snowing today. Very little accumulation of new snow today. Winds were generally light, gusting moderate, on ridgetops from 2-3:30 PM. We found about 8" (20cm) of storm snow at lower elevations and about 12" (30cm) above 8500'.

Snowpack Observations

Lower elevations: razor crust on the surface in the flats and on solars, unsure whether if formed today with the sun out in the AM and early afternoon or yesterday due to warmer temperatures? Some dirty shears on storm snow instabilities and above+below the Feb 2-3 storm/wind event.
Middle elevations: no crusts observed in the upper pack, but we weren't on solars very much. Same dirty shears in storm and recent snow.
Upper elevations: relatively thin wind slabs below cornices in exposed N-NE-E-SE facing terrain, no naturals observed. Same dirty shears in storm and recent snow.
HS=120-170cm middle and upper elevations. No formal snowpack tests performed, strictly hand pit tests in upper 50cm.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wind Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Layer Depth/Date: 20-40cm, past 72 hrs
Comments: Specific to at and immediately below ridglines on certain aspects at upper elevations. Sensitivity is a bit of an educated guess as we spent very little time playing with the wind slabs and cornices.

Terrain Use

Family sled and ski outing, so we were very rarely in avalanche terrain. We skied small sheltered slopes 30-35* but otherwise were on slopes less than 30*.