Sawtooth Avalanche Center

Pro Field Report

Basic Information

Observation Details

Observation Date:
June 1, 2022
Submitted:
June 1, 2022
Observer:
Pro
Zone or Region:
Challis Area and Lost Rivers
Location:
Lost River Peak - Super Gully (S-W; 7600-11,000')

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Snow Stability

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

Bottom Line

There was way more snow than I was predicting based off the Hilts Creek Snotel (SWE 1.5"). We found close to 1 meter of new snow since 0529 and a widespread Wet Loose cycle yesterday afternoon on S-SW aspects. Within the new snow, there were two distinct hardness changes that warranted attention. After some mixed stability results, we chose to retreat from the objective.

Media/Attachments

Advanced Information

Weather Summary

Cloud Cover:
Partly Cloudy
Wind:
Light , SW
New/Recent Snowfall:
HN24: 5cm, HST: 95cm

Clear skies this morning with clouds forming over the mountain tops in the Lost and White Knobs. Strong solar radiation on exit in the lower elevations.

Avalanche Observations

There were numerous D1-1.5 Wet Loose avalanches on S-SW-W of all elevations. It seems like there was a clearing yesterday afternoon and/or increased ambient temperatures that triggered this natural cycle.

Snowpack Observations

I dug two test pits on the ascent and found two distinct hardness changes during the storm. After looking at the Hilts Creek snotel data, there were two small breaks in snowfall which align with the layering. The second pit at 11k produces one ECTP27 dn 30cm. Two more ECTs didn't reproduce the same results, but with multiple CTM SP on that same layer, it was enough uncertainity to pull the plug on going up further.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wet Loose
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Comments: Natural cycle backed this evidence up.
Storm Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
Layer Depth/Date: 30cm/0530
Comments: ECTP27 x1, CTM SPx3

Storm Slab is a short term problem that will likely heal within the next 24 hours or be tested by today and tomorrow's warming trend.

Terrain Use

I went into the day with an Assessment mindset as I haven't been into the Lost River Range this season and there was a new snow load. We avoided going up higher as the HST kept increasing with elevation and it seemed the safety marign was decreasing with a large amount of new snow. The Super Gully is not a great terrain feature to go for a ride in and we were approaching the steep headwall.