Pro Field Report

Basic Information

Observation Details

Observation Date:
December 28, 2020
Submitted:
December 28, 2020
Observer:
SAC - Savage, O'Connor
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Baker Ck (6600-9100', most aspects)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
Widespread
Widespread collapsing 1-3m, a handful of 5-10m. No "rumbling collapses" traveling off into the distance. Only slides observed were a few loose snow D1-1.5 slides on E/SE aspects near Lorenzo Peak in the Boulders - guessing they were yesterday, but could have been today.

Snow Stability

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

Bottom Line

Terrible snowpack structure (soft slab over well developed facets buried on Dec 11th) + widespread collapsing + poor stability test scores = a lot of uncertainty and a chance of remotely triggering avalanches. The snowpack is adjusting to the load from the past couple weeks of snowfall, and the slab is only about a foot thick in this area. BUT, we didn't trust it and traveled very conservatively - especially in areas where the wind had stiffened layers in the upper foot of the snowpack at all. SW and S aspects had a better looking snowpack, and we didn't experience any collapsing or signs of instability on these aspects.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Temperature:
single digits and teens F?
Wind:
Calm

Some light wind on the ridgetops around 9000', but about as calm as it gets for this area. Some evidence of isolated wind loading during and immediately after the last storm.

Snowpack Observations

50-90cm snowpack depth. As expected, lots of weak faceted snow in the middle of the pack on shadier aspects (W-N-E-SE). On sunnier slopes (just south of due W-SW-S), stout crusts in the middle and lower pack. See SnowPilot profile and photo.

Snowpack on a NW aspect near 8800' in the Baker Ck drainage. This site had some wind-effects, and we experienced widespread collapsing in this area.
Snowpit profile on a NW aspect near 8800' in Baker Creek.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Persistent Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 20-35cm
Weak Layer(s): Dec 11, 2020 (FCsf)
Comments: Guessing a bit on sensitivity, probably reactive but trending towards stubborn. Problem most concerning on shady slopes 8000-9000' where weak layer was very well developed and wind had stiffened the snow above the weak layer.

Terrain Use

We stayed out of all large avalanche paths, all starting zones over 35*, and alll wind-loaded starting zones. We were conservative going into the day, and we didn't see anything to change our minds.