Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
March 31, 2020
Submitted:
March 31, 2020
Observer:
SAC - Savage
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Galena Summit-Avalanche Peak area: 8200-9400'

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
Isolated
Collapsing? 
None Experienced
Cracking in fresh wind drifts, extending up to 20 feet. I observed some small sluffs involving all the new storm snow in very steep terrain (>40*) along the road.

Snow Stability

Stability Rating: 
Poor
Confidence in Rating: 
High
Stability Trend: 

Bottom Line

Today was a real "storm in progress" day - a good day to avoid all avalanche terrain. By 5:30 PM, there was 12-18" (30-45cm) of new snow being blown around by gusty W winds. Isolated wind slabs existed in middle elevation terrain. Snowpack tests produced some unstable results in shady terrain on weak, faceted snow about 2 feet below the surface. The new snow appeared to be bonding fairly well to moist crusts on more southerly aspects. There were some density changes within the new snow that could create failure layers for wind slabs at upper elevations. I left before the earthquake hit.

Advanced Information

Weather Summary

Cloud Cover:
Obscured
Temperature:
20s F
Wind:
Moderate , W

Snowing S1-5 (half an inch to 2 inches per hour) from 3-5:30 PM. 12-18" (30-45cm) storm snow with drifts to 2 feet thick at middle elevations. Wind was actively transporting snow.

Snowpack Observations

8600' E-NE (see photo): HS=180cm 45cm storm snow, razor crust and FC under that, then series of crusts+FC and mixed forms to subtle dirty FC layer 70cm down: ECTP16, 110cm on dirty FC; ECTN11, 135cm on razor cruts/FC at recent interface; ECTN4, 160cm mid-storm layer.

9000' NW: HS=182cm 37cm storm snow, interfaces and crusts and FC below that were there but not as well developed as in 8600' E-NE pit location: ECTN3, 168cm on mid-storm layer; ECTN12, 145cm on old/new interface FC; ECTN16, 135cm on FC (3/14?); no break or shear on dirty FC layer at 120cm (62cm down from surface)

(3-31-2020) Pit near Galena Summit (Avalanche Peak) at 8600' on an E-NE aspect. A layer of weak, faceted snow buried about 2 feet deep produced unstable test results. The same layer has been responsible for avalanches just west of this zone before the recent storm.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Persistent Slab
Isolated
Specific
Widespread
Unknown
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Layer Depth/Date: 60-75cm
Comments: The facets that formed in early to mid-March exist here. We'll see if they become a problem like in the western Smoky Mtns (Headwaters, Frenchman Ck, Smiley Ck, Beaver Ck) - I don't trust them for now, guilty until proven innocent.
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: 40-60cm
Comments: Drifts and small slabs were forming in places that typically don't see much wind affect. Wind slabs are likely the primary problem at upper elevations.

Terrain Use

I stayed out of avalanche terrain. The hazard was building while I was out from 3-5:30 PM.