Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
November 23, 2022
Submitted:
November 23, 2022
Observer:
NWAC Forecaster - Katie Warren
Zone or Region:
Stevens Pass
Location:
Stevens Pass (4000-5700ft, all aspects)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
Isolated

Media/Attachments

Small wind slab near a ridge line at Stevens Pass. East aspect at 5000ft.
West aspects near ridgelines at Stevens pass were scoured down to a melt freeze crust. The small drifts of snow behind these trees and shrubs give you a good indication of the wind direction, right to left, in this photo.
Snow profile at Stevens Pass: 5700 ft on a northeast aspect. No notable stability test results.  
Steep southern aspects with low snow coverage at Stevens Pass.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Sunny
Temperature:
34°F
Wind:
Calm
New/Recent Snowfall:
HST @ 5700ft : 28cm

Temperatures increased from 30F to 34F throughout the day. Shady slopes felt cold, while sunny terrain was warm and quickly melting snow off of the trees. The winds were calm throughout the day and we enjoyed mostly clear skies.

One small (D1) avalanche was observed in wind-affected terrain on an east aspect at 5000ft.

Snowpack Observations

We traveled from 4000-5700ft on various aspects.

4000ft: HS=40cm, HST=20cm
5700ft: HS=87cm, HST=28cm
Steep southern slopes held significantly less snow.

At 4000ft, a 2cm thick melt-freeze crust existed with a dusting of dry snow on top. Above 4500ft, the crust was no longer present.

The top 4-10cm of the new snow had a wind-drifted feel in more open areas. Near ridgelines, winds had scoured west aspects down to a melt-freeze crust. We dug a pit at 5700ft on a northeast aspect. The inversion that brought warm air to the upper elevations had heavily affected the snowpack at this elevation. While I could identify a weak layer of faceted crystals, they were moist and significantly rounded. We experienced a small localized collapse in a lower elevation sheltered location where cooler temperatures better preserved this weak snow layer.

As temperatures increased throughout the day, southern slopes in direct sun became moist, and we observed some rollerballs off steeper terrain.

Overall, we found decent skiing conditions despite the depth and surface texture variability due to the strong winds accompanying this storm.

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