Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

On Saturday, another windy burst of snow will bring very dangerous conditions to upper elevations. You can trigger avalanches in recent snow on slopes steeper than 35 degrees. Minimize the risk of getting caught in an avalanche by sticking to lower-angle terrain and avoiding steep roll-overs and slopes above rocks or cliffs. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1.5–2.5

    Travel at upper elevations is not advised. Stick to wind-sheltered terrain less than 35 degrees, and well out from under steep, overhead slopes. Steer around typical trigger points like convexities, and unsupported, "hanging" features. Stay off of steep, leeward sides of ridges where the wind will drift deep slabs. Watch for cracks shooting through the snow and recent avalanches to indicate the danger. 

    You may be able to trigger small avalanches in the new snow even on wind-sheltered slopes over 35 degrees. Use small features and quick tests to see how easily the snow slides before moving onto larger slopes. While it's becoming unlikely, there's a chance that you could trigger much deeper avalanches on a layer from the beginning of the week. Dig down about 2-3 feet and use snowpack tests to locate this layer, just above a crust. 

    (12/8/2024)

    At the crown of a small (D1, 24cm deep) skier triggered wind slab avalalanche. Mill Creek, 5,400ft, SE

    Photo: Josh Hirshberg

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–1.5

    Warming temperatures will bring wet avalanches to low elevations. Keep an eye out for recent avalanches and rollerballs in moist snow to indicate that you could trigger a slide. Even small, wet avalanches can be forceful enough to push you into rocks or trees. You can avoid these avalanches by staying above the elevation of moist snow or sticking to lower-angle slopes. 

    (12/23/2024)

    A natural loose wet avalanche (D1) occurred above Valhalla Lake. 5,400ft, W.

    Photo: Josh Hirshberg

Avalanche Discussion

Another storm will impact the Stevens Pass zone with over a foot of snow forecast with strong winds by Saturday evening. Friday was relatively quiet following a storm that brought over 19" of snow and widespread triggered slab avalanches on Thursday. Observers reported avalanches in the new snow, with many big enough to bury a person (size D2). 

While storm instabilities appear to be resolving after a couple of days, a weak layer buried on the 22nds is one to watch. You can find it 2-3 feet below the surface, and just above a thick series of crusts. This layer was the culprit in a few larger avalanches triggered by Stevens Pass patrol on the 26th, and by backcountry skiers on the 24th on Rooster Comb and Lake Susan Janeoutside Stevens Pass Ski area. NWAC Forecasters near Lake Susan Jane and Lake Valhalla reported lingering instabilities that matched the recent avalanches. While mostly the interface consists of stellars (snowflakes) some profiles have revealed small faceted grains.

If you're in the mountains, let us know what you see by submitting an observation.

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