Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
January 15, 2020
Submitted:
January 15, 2020
Observer:
SAC - Davis, Liles, VandenBos
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Galena Peak

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
Isolated
Cracking and collapsing occurred under recent storm snow on facets in low and middle elevation S-W facing terrain.

Snow Stability

Stability Rating: 
Fair
Confidence in Rating: 
Moderate
Stability Trend: 
Steady

Bottom Line

The snowpack is still adjusting to a load of new storm snow + wind-blown snow. Cracking and collapsing occurred in both sheltered and subtly wind-affected terrain. Drifts at middle and upper elevations were multiple feet thick.

Advanced Information

Weather Summary

Cloud Cover:
Partly Cloudy
Wind:
Moderate , SW

Some sun to start the day followed by clouds and then clearing again later in the afternoon. Steady moderate wind at the start of the day that mixed into valley bottom by the end of the day.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Comments Photo
2 Senate Peak
S 10,000
D2 Crowns were no longer visible due to additional wind-loading. None
2 Galena Peak
NW 10,000
None
2 WRV - Timber Gulch
SW 6,700
D1.5 SS Likely occurred on Tuesday afternoon during outflow wind. Cross-loaded sub-ridges. None

There were no obvious larger slides in the Boulders. However, due to recent wind-affect, I'm sure there was more activity than we were able to see the remnants of today.

Snowpack Observations

No formal tests but lots of pole-pokes and hand pits revealed anywhere from 40 cm 4F slabs in sheltered areas to multiple foot thick drifts in exposed terrain–both sitting over weaker snow layers near the ground.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wind Slab
Isolated
Specific
Widespread
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Comments: Also present at exposed middle and more isolated pockets near valley floor. Multiple wind directions have built slabs on various aspects.
Persistent Slab
Isolated
Specific
Widespread
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Comments: Lots of weak snow deeper in the snowpack. Wind-affect will make this problem worse, but we also experienced signs of instability in relatively sheltered terrain.

Terrain Use

We avoided obviously wind-loaded avalanche terrain. We became more conservative after finding a stiffer than expected slab in relatively sheltered terrain.