Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
February 13, 2020
Submitted:
February 13, 2020
Observer:
Lundy, Stefan
Zone or Region:
Sawtooth and Western Smoky Mtns
Location:
Williams Peak Hut area

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
None Experienced
Collapsing? 
None Experienced

Snow Stability

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

Bottom Line

Main objective today was to gather baseline snowpack data for Martin's research project and do some terrain familiarization. Overall, the snowpack seems stable. Lingering concerns include isolated wind slabs in alpine terrain and the unlikely possibility of triggering a deep slab in very steep, rocky, alpine terrain. Intermittent moderate winds at upper elevations did not seem to be moving much snow.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Wind:
Moderate , SW

Moderate winds were intermittent and there is not much snow available for transport.

Snowpack Observations

Snow surfaces are quite weathered from recent winds coming from many directions. This is true even on mid-elevation slopes unless they are very sheltered. The wind effect and warm, inverted temps seem to have inhibited the near-surface faceting process to a large extent. Surfaces at lower elevations were more faceted. I could see some potential instability with the weekend storm but it doesn't seem likely that it will be extensive or long-lived in this area.

Mid elevation solar slopes seemed fairly cold, and while we didn't travel on steeper slope angles, we did not find widespread sun crusts.

HS at the Williams Peak Hut (7900') was 120cm.

@8300', E: HS 165cm. 11/26 was 150cm down and presented as a 5cm layer of 4F 3-5mm DH/FC over a MFcr just above the ground. There was around 100cm of P hard snow above it. There were no other weak layers found in the pit. An ECT produced no results. A deep tap produced DT22 SC on 11/26.

Avalanche Problems

A persistent slab may (?) be possible in rocky, shallow, alpine terrain. In the mid-elevation terrain where we dug, it seems almost impossible to trigger where the snowpack is uniformly deep.

Terrain Use

We stuck to slope angles less than 35 degrees primarily for work objective purposes.