Northwest Avalanche Center

Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
January 27, 2023
Submitted:
January 27, 2023
Observer:
NWAC Forecaster - Matt Primomo
Zone or Region:
Stevens Pass
Location:
Skyline

Signs of Unstable Snow

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

Media/Attachments

Profile from a NE aspect at 5,200ft. Sudden planer failures, and some potential for propagation was observed on the MLK crust.
Mount Mastiff with some subtle wind ripples, indicating cross drifting.
Very steep east facing slopes beneath Rock Mountain.
Whitepine Cirque and some wind drifting.
Some signs of drifting approaching the windward side of a ridge.
East facing slopes near treeline with some light wind drifting over an old skin track.

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Wind:
Light , W

Gusty winds with warm air near Berne, lighter winds and cooler on the pass. East of the pass I could see clouds shrouding, and snow drifting on the higher peaks of the zone.

Noticed a couple small/narrow, few day old wet loose slides on S aspects of Lichtenberg.

Snowpack Observations

Found 3-4" of new snow above 4,500ft, less lower down. The new snow was sticky and roller-balled on lower elevations. I got the sense you could trigger a small loose wet slide in the right time and place today. Higher up, the new snow was drier but still dense. I noticed some drifting, covered skin tracks, etc but wind effects were fairly minimal at the highest elevation I made it to (5,400ft). I could get some minor cracking on test slopes, where the new snow was fracturing on the recently buried crust about 6" down.
I dug two test profiles, one on a SE aspect at 5,200ft the other on a NE aspect at 5,200ft. 4" of new snow on a 1" thick melt freeze crust. About a foot down to the MLK crust, which is a translucent freezing rain crust. I found moderate, resistant planer hand shears with weaker snow above this crust, and easy to moderate sudden planer results with compression tests. Some tests would cash register slide off the column after fracture. A propagation saw test on NE was 55/100 (End).
With a loupe, I found a couple inches of rounding facets above the crust (0.5-1.0mm). Hardness was 1F-. Overall, I got a sense this layer is gaining strength, but the snow above still isn't bonded super well.

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