Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

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

Conditions will be dangerous, and wet avalanches will run naturally as temperatures warm and rain falls to upper elevations. We anticipate small avalanches, and there's a chance for larger, more destructive wet slides. If you see heavy rainfall or large wet slides, avoid being on or under all slopes steeper than 30 degrees.  

Avalanche problems

  • Wet Slabs

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

    Even in Considerable danger, you can still see natural avalanches. Small, wet loose avalanches will be likely. There's a chance for larger avalanches, including wet slabs on deeper weak layers. Stay out from under rock slabs, where you could see wet avalanches involving the entire snowpack. Look for signs of instability, including rollerballs, recent avalanches, and wet snow that slides easily on small test slopes. If you see these, stay off of slopes steeper than 35 degrees, especially where you could be pushed into rocks or trees. Make sure to stay well out from under slopes where avalanches could come down from above. 

    Upper elevations and slopes above 5,000ft could be most dangerous as they hold the greatest potential for large avalanches. If the rain breaks down a sub-surface crust, we could see larger avalanches at middle and lower elevations. The rain could also weaken an existing poor structure, making triggering avalanches on the Solstice crust easier. If you experience whumphing collapses or see large avalanches, stay off of and well out from under large open slopes and terrain features. 

    (12/10/2023)

    An example of a wet slab avalanche from earlier this season.

    Photo: John Merriwether

Avalanche Discussion

As of Friday evening, there's 4-6" of settled storm snow, moist at low elevations resting on a crust that formed on Tuesday up to 5,000ft. 

On Wednesday, an observer reported a large whumphing collapse on a southerly aspect near Rainy Pass. At Stevens Pass resort, snow safety reported small sluffs running on the new crust (1/24) with ski triggering. A widespread wet loose cycle occurred on Tuesday with light rain falling on the previously dry snowpack. These ran in the D1-1.5 range, but a handful were D2's (Lichtenberg), and perhaps one D2.5 (West Camp on S side of Rock Mtn).

Some very large avalanches ran on deeper weak layers within the Solstice Crust sandwich earlier in the month. Regionally, very large slides have been triggered on a similar old crust layer at Mission Ridge on Wednesday and Crystal Mountain on Tuesday (see photo). This crust and facet complex is now 4-5 feet below the surface in much of the zone. Last week, observers reported sudden and propagating test results on this weak layer. If you venture to the eastern half of the zone, it would be worth reading the East Central forecast. If you make it out, please share what you found with an observation.

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