Close
Payette Avalanche Center

Public Observation

Observation Details

Observation Date:
December 12, 2021
Submitted:
December 13, 2021
Zone or Region:
Big Creek Summit
Activity:
Skiing/Snowboarding
Location:
Big Creek summit

Signs of Unstable Snow

Did you see shooting cracks? 
No
Did you experience collapsing or whumpfing? 
Yes, Isolated

Observations

Snotel at big creek showed 1.5 inches of SWE and 10 inches of snow in 24 hours (Saturday-9am-Sunday9-am.

Tough travel and trail breaking conditions in the unconsoliand snow. No whumping, but isolated cracking over shrubs and near rocks (photo 1). Strong cross winds from the southwest were forming wind slabs along the ridges

I Dug a pit on a wind sheltered 20 degree slope on a west aspect at 7134’.
Total snow depth was 90 cms.
Low scores in compression tests with the new snow failing at the density changes from within the storm. My Extended column test did not propagate, as the new snow collapsed on itself without cohesion. It lacked slab characteristics in this wind sheltered location.

On and off snow showers all day with a continued strong breeze out of the south. New snow changed to graupel during the day with a temperature increase. By afternoon, the snow had already settled a bit from the morning, but descending was still “trenching” and treacherous.

Main hazards included newly formed wind slabs, thin early season conditions, rocks, stumps, and the driving.

Side note-as of 6:00 am Monday morning, the snotel is reporting another 1 inch of SWE and 7 inches of snow depth in less than 24 hours.

Media

Cracking and settlement of new snow near rocks.
Snow pit photo with layers
Strong winds forming wind waves and such along the ridges.
Graupel snow during afternoon warmup.
Close