Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
November 30, 2022
Submitted:
December 1, 2022
Observer:
SAC - VandenBos (off duty), Jorgenson
Zone or Region:
Soldier and Wood River Valley Mtns
Location:
Warm Springs Creek Drainage (6,300-8,300', primarily E-NE-N-NW)

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
Widespread
Collapsing? 
Widespread

Snow Stability

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

Bottom Line

A very weak snowpack exists in this area. The 8-10" of new snow was begging to overload the weak snow underneath and widespread cracking and collapsing were observed. On steeper slopes or where the wind was building slabs, I have no doubt that avalanches would have been easy to trigger.

Media/Attachments

https://youtu.be/bNTa5T0DFIk

Advanced Information

Weather Summary

Cloud Cover:
Obscured
Wind:
Calm
New/Recent Snowfall:
20cm at road level, 25cm at our highpoint

Steady S1-2 snowfall throughout afternoon tour, with accumulation of 5-7cm between 1400 and 1800.

Avalanche Observations

No avalanches observed, aside from micro-avalanches on small rollovers, but we had very limited visibility.

Snowpack Observations

Impressive collapsing and shattering of slopes, particularly as we climbed higher where there was more older snow to smooth out the terrain. Thanks to ongoing snowfall and poor light it was difficult to tell how far these were traveling, but in a few instances it was evident that these were running 100+m across and upslopes. Remote triggering would certainly have been on the table where the wind was building a slab in steeper terrain.

The 11/27 interface

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
Weak Layer(s): Nov 27, 2022 (FC)
Comments: Rose shaded based on where this layer is expected to exist. Its character varies by aspect and elevation and its sensitivity does as well.