Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

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Out of date — this forecast expired 3 years ago.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

Highlights

The storm may have ended but dangerous avalanche conditions could persist at mid and upper elevations. You may trigger or see natural avalanches on steep sunny slopes and where the wind drifted the snow deeper.

Avalanche problems

  • Loose Wet

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

    This avalanche problem hinges on the sky. A race will ensue Tuesday between clearing morning fog and increasing high clouds. If the sun comes out for any meaningful length of time, you should see the snow start to shed from trees, rocks, and steep faces. This will likely trigger natural loose wet slides. So, if you start to notice the sun and begin to peel off layers, the bet is the snowpack won’t be far behind. 

    Keep an eye on the terrain above you. Don’t linger under steep sunny slopes. While most of these slides should stay relatively small, at mid-elevations, they could entrain enough snow to bury or kill you.

  • Wind Slabs

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

    Windy conditions Monday night into early Tuesday morning could build a fresh batch of slabs at mid and upper elevations. Since they are brand new, these slabs could be fairly easy to trigger. Look for clues like textured surfaces, cornices, and drifts to point toward wind-loaded slopes. You’re most likely to encounter wind slabs near exposed ridges, in the tops of chutes, on convex rollovers, and along the base of cliffs. 

    Give firm pillow-like drifts a wide berth. Instead, seek out more sheltered or lower angled terrain to avoid this problem.

    (2/18/2023)

    Obvious signs of wind loaded snow. 

    Photo: Dallas Glass

Avalanche Discussion

Ahh, the post storm transition day… These are always tricky. Soft snow and blue skies can beckon, but we often have a higher degree of uncertainty. Observations from Monday were limited due to the stormy weather. Consider easing into the terrain by using smaller lower consequence slopes to see how the snow reacts before committing to larger features. 

As of Monday afternoon, the Pass has received 7-10 in of snow. This buried the new 3/12 interface. While we don’t expect any weak snow at this layer, information is scarce. You can use up track tests and hand pits to investigate this interface as you travel. If you see cracking or the new snow failing in blocks, avoid nearby steep open slopes. 

Avalanche professionals reported lots of rollerballs due to the lower elevation rain and wet heavy snow Monday. Drier more winter-like conditions were encountered about 4000ft in the Alpental Valley. 

With the recent warm temperatures and rain, other issues like glide avalanches and natural cornices failures are on our minds. If you see crevasse-like cracks or overhanging blocks of snow, keep moving. Don’t hang out under these looming unpredictable hazards.

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