Pro Field Report

Basic Information

Observation Details

Observation Date:
February 13, 2023
Submitted:
February 14, 2023
Observer:
SAC - VandenBos (off duty)
Zone or Region:
Banner Summit
Location:
Copper (7,100-8,900', primarily north half of compass)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
None Experienced
Avalanches observed refers to very small natural and triggered slides described below (see photo). I experienced some cracking in freshly deposited wind drifts. Drifts were up to 15cm thick.

Snow Stability

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

Media/Attachments

These very small wind slabs failed naturally on Copper Mountain on the evening of 2/13. They released on a NE aspect at 8,800'. Similar small slides were easy to trigger.

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Wind:
Moderate , W
New/Recent Snowfall:
4-5cm at highway at 2000

During the day in Stanley: clear skies for much of the day, allowing for plenty of direct solar input. Cloud cover increased rapidly in late afternoon, with sputtery graupel showers starting around 1600.
Afternoon/evening tour: Snowing S1 to S2 throughout duration of tour, with winds moving the new snow at all elevations. 4-5cm accumulation at highway by exit from field at 2000. Continued to snow S2 throughout duration of drive back to Stanley, with lots of drifting going on at highway level.

Avalanche Observations

I encountered some very small wind slabs in upper elevations that had released naturally (5-10cm thick, 1-5m wide, ran 20-30m downslope). I was able to intentionally trigger similar slides with ski cuts. These did not pose much of a hazard, due to their very small size.

Snowpack Observations

Plenty of solar input for much of the day, suspect the wet loose problem may have turned on again in steep solar terrain in the Sawtooths today and that recent crusts+facets on solars may have been put away warm. Warm temperatures over the past few days did not generate crusts on shaded slopes.

Lots of snowing and blowing going on up on Copper this evening. I encountered some very small wind slabs in upper elevations that had released naturally (5-10cm thick, 1-5m wide, ran 20-30m downslope). I was able to intentionally trigger similar slides with ski cuts. These did not pose much of a hazard, due to their very small size. Winds were blowing at all elevations, though most of the constructive slab building was going on at upper.

Terrain Use

I felt comfortable entering avalanche terrain while managing minor new snow instabilities.