Pro Field Report

Basic Information

Observation Details

Observation Date:
March 20, 2022
Submitted:
March 21, 2022
Observer:
SAC - VandenBos
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Camp/Rainbow Creek (7,600-9,200')

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
Isolated
I experienced a few small collapses when traveling on low angled solars, these seemed to be involving facets sandwiched between crusts. Avalanches observed refers to the slab avalanche in the Cabin Creek drainage described below and some apparently fresh wet loose debris on steeper terrain in the Sawtooths. I'm unsure on the timing of both of these, likely in the past few days at the oldest.

Snow Stability

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

Media/Attachments

This recent slab avalanche was observed on Cabin Peak in the southern Sawtooths. It failed well below the ridgeline on a slope that appears to have been affected by the wind. This slope faces E at 9,700'.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Wind:
Moderate , N
New/Recent Snowfall:
2cm

Avalanche Observations

I glassed a slab avalanche that failed on Cabin Peak

Snowpack Observations

My primary objective was to look at weak layers in the upper snowpack on a variety of aspects in untraveled terrain in this area. The "slab" I encountered (15-20cm) at the surface was thinner than what has been reported on the Titus side of the pass. Around 8,000' the 3/8 weak layer and the variety of older weak layers (1/20 and onward) are tightly sandwiched together and separated by a variably thick crust that formed during the warm wet storm at the end of Feb/beginning of March. As you gain elevation from there, a series of separate crusts with associated facets becomes more apparent. Without a significant slab on top of any of these it is tough to say with any certainty how they would/will behave once loaded... A quick 1+" of water would be very likely to produce some interesting avalanches, but it doesn't seem like that's in the cards.
It will be interesting to watch how the thick stack of well-developed facets that exist on shaded slopes will transition to a spring-time snowpack. It seems like that may happen after we finish forecasting for the year, but hard to say. I can imagine seeing some sizeable gouging wet loose on shaded aspects when/if meltwater saturates the upper snowpack.

Terrain Use

I didn't enter avalanche terrain steeper than 35 degrees and had not planned to.