Pro Field Report

Basic Information

Observation Details

Observation Date:
November 29, 2020
Submitted:
November 29, 2020
Observer:
SAC - VandenBos (off duty), Peterson
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Butterfield

Signs of Unstable Snow

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

Snow Stability

Stability Rating: 
Very Good
Confidence in Rating: 
Moderate
Stability Trend: 
Steady

Bottom Line

Thin, weak snowpack, but no overlying slab...yet.

Media/Attachments

Thin, weak snowpack on north facing slope at 8,500' on Butterfield in the Galena Summit and Eastern Mtns Zone.
Thin snowpack with crusts in the middle of the pack and at the surface. SE facing slope at 8,800' on Butterfield in the Galena Summit and Eastern Mtns Zone.

Advanced Information

Weather Summary

Cloud Cover:
Clear
Temperature:
teens to low 20s F (estimated)
Wind:
Calm

Another calm, cool, sunny day. HST=5cm (11/25).

Snowpack Observations

Thin snowpack (20-35cm on middle elevation solars, 50-60cm on shaded aspects) is showing signs of faceting throughout. Most pronounced at surface and in upper half, but beginning to be evident in lower portion as well. Shaded aspects are beginning to produce some basal facets, these are dry and still relatively small (1-2mm) but distinct from the faceting snow above. Found some small (1-2mm) surface hoar at 11/25 interface on shaded slopes, not sure how widespread this layer is or if it will be distinguishable from the current snow surface once loaded. In either case, I'd expect the current surface to produce signs of instability and avalanche activity as loaded. As found further north, 11/17 interface is quite obvious in pit walls thanks to the dust accompanying it. On shaded slopes this interface is about 30cm down. On solars it is about 15cm down and manifests as a 2-3cm melt freeze crust. Stability tests produced ECTNs at 11/17 with moderate to hard force on both aspects.

Avalanche Problems

No significant problems encountered. Suspect isolated wind slab problems present in upper elevation, exposed terrain.