Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Happy New Year! Ring in the new year by choosing conservative routes and staying away from slopes greater than 35 degrees. A recent natural storm slab avalanche cycle Thursday highlights the risk within the recent snow. As temperatures warm and rain falls, the snowpack at mid and lower elevations could become wet and slide downhill.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    As temperatures warm and rain reaches well into the near treeline band you could see the snow surface become wet and unstable. The relatively modest expected precipitation totals should help limit the wet avalanche activity. If you see new rollerballs or find the snow surface becoming wet and heavy, steer around steep open slopes. Many of these wet avalanches may take some effort to get moving, however, if they do start they could entrain the recent snow and become large and dangerous.

    (11/27/2020) Rollerballs like this are a great clue the snow surface is becoming wet and unstable.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2

    A natural storm slab cycle occurred in some parts of the Stevens zone very early Thursday morning. While these storm snow layers should gain strength, they can still trigger under your weight Friday. Give these weak layers another day to heal, and stay off of open slopes greater than 35 degrees. Avalanches may trigger more easily on steeper rockier terrain and in locations where the wind drifted the snow deeper. Use small slope tests and hand pits to highlight layers of concern in the upper snowpack. The most recent interface (12/29) served as the weaklayer in several avalanches in nearby zones.

    (12/31/2020) Example: West-South Zone: Shooting cracks on a small slope test in wind drifted snow. NE 6400'.

Avalanche Discussion

Stevens Pass received quite a bit of snow in these recent storms (18-24”). This adds to the snow above several interfaces we are tracking. If you dig the most consistent and prominent snowpack marker maybe a stout crust buried on 12/21. Weak snow grains were reported a few inches above this layer. At this point, 3-4 ft may exist over these concerning grains. 

Oscillating temperatures and moderate winds during the recent storms may have helped cornices grow larger along ridgelines. Give these newly formed and weak cornices a wide berth. They may fail much further back from the ridge than you expect. 

Happy New Year from all of us at NWAC!

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