Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
April 15, 2022
Submitted:
April 15, 2022
Observer:
SAC - Scott Savage
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Galena Summit - Cross area (S-SE-E-NE-N-NW: 8300-9200')

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
Isolated
Collapsing? 
None Experienced
I triggered a baby drift/wind slab at 9200', SE aspect, about 20' wide and 1 ft thick. It only extended about 5 ft below the cornice. There was 1-2 ft of new cornice growth at most, less than that for the most part.

Snow Stability

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

Bottom Line

I found isolated wind slabs right at exposed ridgelines near 9200', but they did not extend far enough below the ridges to be a hazard in middle elevation terrain. With significant previous and ongoing wind transport, alpine terrain in this area is likely far more dangerous. Very steep, sunnier aspects in sheltered terrain were turning to mush and could have become a problem this afternoon after I left. For Saturday's storm, there are going to be 2 potential weak layers in the upper snowpack on sunnier aspects in this area: crusts and facets that formed at/near the surface today, and thin crusts and facets that formed earlier this week (about half way from today's surface to the old, hard crust).

Media/Attachments

Small wind slabs around a foot thick were confined to immediately beneath ridgelines in middle elevation terrain near Galena Summit.
https://www.instagram.com/p/CcZCyu6FJ8R/

Advanced Information

Weather Summary

Cloud Cover:
Partly Cloudy
Temperature:
Teens and 20s F
Wind:
Moderate , W
New/Recent Snowfall:
HST=25cm (10") at 8300' at the road and 40cm (16") on shady terrain 8800-9200'

Cloud cover decreased from 11-3:00. Gusty, moderate W winds were moving snow all day in exposed middle elevation terrain. Today's sun is sprobably limiting the snow available for transport on solar aspects going forward, but there is plenty of snow available on shadier slopes and at upper elevations.

Snowpack Observations

Storm snow/old interface was not very sensitive where I traveled (mostly NE-E-SE-S, a little bit on N-NW). No obvious mid-storm layers in shady terrain.
Surfaces: I observed a crust and FC combo forming on NE-E-SE-S below 8700' and on E-SE from 8800-9100'. No crusts forming in the windy zone above 9100'. I expect the surface crusts to form on SW-W-NW below 8700' and S-SW-W from 8800-9100' where I was today. More northerly slopes stayed dry.
Upper snowpack below surface: Ski penetration = 10cm on solars and 20-30cm on shady, staying above the old hard crust. Boot penetration = to the old crust (15-20cm on solars). The sun made the upper 10cm moist on solars/sunny slopes. There was a thin crust+FC combo buried about half way down in the storm snow, likely from Tues or Wed. The moist surface snow wanted to move on the Tues/Wed interface on very steep slopes and cracked a few feet out in front of me a couple times.
No observations below the most recent, stout ice crust.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wind Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Layer Depth/Date: 20-40cm
Comments: Location rose shows where I observed the problem. I ski cut one baby wind slab, see photo. Wind slabs isolated to right beneath prominent middle elevation ridgelines near 9200' where I traveled. Up to 2 ft of new cornice growth, but mostly less than a foot. Alpine terrain would be a different beast (more dangerous).
Wet Loose
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Layer Depth/Date: 10-15cm
Comments: Location rose shows where I traveled and would have expected wet loose concerns in the perfect terrain (very steep + sheltered + SE-S-SW). On slopes with all of those characteristics, you may have been able to trigger small wet loose slides this afternoon. That terrain did not exist where I traveled.

Terrain Use

I planned to avoid large, wind-loaded avalanche starting zones and hot, sunny, wind-sheltered avalanche paths with terrain traps beneath them. I did not see anything to make me change my mind.