Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
February 12, 2020
Submitted:
February 12, 2020
Observer:
SAC - Davis
Zone or Region:
Soldier and Wood River Valley Mtns
Location:
Soldier Mountains - Couch Summit, Salt Creek

Signs of Unstable Snow

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

Snow Stability

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

Bottom Line

I observed a few older slides that likely occurred nearly a month ago. The Soldier Mountains have not received much new snow since the storm cycle in mid-January. The wind has sculpted upper elevation slopes into a patchwork of icy drifts and scoured ridges. The same can be said for low elevations in the foothills near Fairfield. Beyond Couch Summit, I found much more inhabitable conditions and even soft (faceted) snow.

Beyond the icy, surfaces that one might expect in wind-affected areas, a concerning crust and facet layer sit near the surface on most slopes. I expect this interface to be touchy when loaded with a sufficient slab.

Media/Attachments

Surface hoar was found on many relatively sheltered slopes at middle elevation.
Starting zone of a slide that covered salt-bowns road.
Track and deposition zone of a slide that covered the salt-bowns road.
Heavy scouring on north-face of Peak 2 in the Soldiers.
Alpine wind-affect in the Soldiers.
Debris of older slide that originated in the Soldier Mountain alpine.
Icy wind drifts at low elevations in the Soldiers.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Wind:
Light

Cold in the morning but quickly reaching near freezing at the trailhead. Snow surfaces stayed cool. There were only a few clouds in the Soldiers, Pioneers, and western Smokys. The wind blew light from a variety of directions.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Comments Photo
1 Soldier Mountain Crest
E 9700'
D2 U Old slide initiating from the Soldier Mountain Crest.
Debris of older slide that originated in the Soldier Mountain alpine.
1 Salt-Bowns Road
7400'
D2 HS Heavily cross-loaded pocket lee to north wind. Put 5' of debris across the road.
Starting zone of a slide that covered salt-bowns road.
1
None

No recent avalanches.

Snowpack Observations

The "front-country" of the Soldiers to about Couch Summit were raked by the wind. Large, icy, dune-like drifts sat over a shallow faceted snowpack. There was lots of vegetation to be seen poking through on most slopes.

Beyond Couch Summit, snow depth ranged from 100-140 cm. Snow surfaces were weak. The most concerning was a facet and MFcr combo that I found on all aspects and slope angles below about 8800'. The crust formed at the start of February (2/2). Since then, minimal snowfall has faceted and shady slopes boast a healthy batch of surface hoar. The mid-pack was generally strong, but weak facets sit near the ground.

Avalanche Problems

I didn't encounter an avalanche problem today.

The wind slabs I stomped on were old and unreactive. I imagine you'd need a steep, alpine, icy surface for the chance to find one that may do much.

In the "front-country" closer to Fairfield, I'd describe these drifts to be more of a persistent slab problem with stiff rock-hard slabs sitting on a shallow faceted snowpack. I stomped around on several of these slabs and It seemed hard to imagine triggering a slide.

Terrain Use

Solo mission. I generally stuck to low-consequence avalanche terrain and smaller features.