Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

You can trigger avalanches, on steep, sun-exposed slopes as well as where the wind drifted stiffer slabs of snow, just below ridges. To avoid these avalanches, you can stick to wind-sheltered and shaded terrain and slopes less than 35 degrees. Expect another calm day, warming temperatures, and increasing clouds in the afternoon. 

Avalanche problems

  • Loose Wet

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

    Watch for rollerballs and loose wet avalanches on steep, sun-exposes slope. If you start to see natural activity, even rollerballs, it's time to move to slopes under 35 degrees or more shaded terrain. Avalanches will be possible with the timing of the sun, starting on southeast and later on southwest aspects. Temperatures will be about 5F degrees warmer than Monday, though we expect clouds to limit the sun's effects in the afternoon. 

    (12/9/2024)

    Small skier-triggered wet loose avalanches. Lichtenberg Mtn

    Photo: Katie Warren

  • Wind Slabs

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

    While avalanches in wind-drifted snow are most likely at upper elevations, there's still a chance that you could trigger one on leeward sides of ridges at middle elevations. As the wind tapered off on Sunday night, you'll need to look for clues on leeward slopes where you can trigger avalanches. Look for avalanches, shooting cracks, and stiffer pillows of drifted snow to indicate the danger. Use small test slopes to assess the snowpack before comitting to larger terrain. You can avoid triggering these avalanches by steering around wind features and thicker pillows of snow. 

    (12/8/2024)

    A skier triggered avalanche (D1) in the top 20cm of recently drifted storm snow. Mill Creek, SE, 5,300ft

    Photo: Josh Hirshberg

Avalanche Discussion

On Monday, an NWAC forecaster went to Lichtenberg Mtn. They reported numerous natural and triggered loose avalanches, mostly on steep, sunny slopes.  Otherwise, the recent storm snow was continuing to bond well. Conditions were calm and sunny, with temperatures reaching freezing.

On Sunday, an NWAC forecaster on Stevens Pass found 1 foot of recent snow at low elevations and drifts of 20-28" on mid-elevation ridges. They triggered  avalanches on a couple small wind-loaded test slopes. The crowns were 8-10" deep, and the slides ran until slope angles dropped below 35 degrees. During avalanche mitigation work, Stevens Pass ski patrol triggered numerous small avalanches, up to size D1.5, in steep terrain around 5,500ft. These were all running within the top portion of the new snow. 

From December 7-8th, a major storm brought just under 2" of water equivilent to the Stevens Pass area. The first half fell as rain, wetting the old snow and likely destroying the host of weak layers. Below about 4,700ft, you can find the 12/7 interface still moist and unfrozen under about a foot of new snow. As you go up in elevations, you'll find more new snow and that the 12/7 crust is harder and frozen. Generally, the new snow is "right side up," progressively harder with depth, and well-bonded to the 12/7 interface.

 

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