Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Wednesday could be a very tricky day with dangerous avalanche issues and rapidly changing conditions. You will even see natural avalanches due to sunshine and warm temperatures. Choose terrain with plenty of options that allow you to easily avoid avalanche terrain if necessary.

Avalanche problems

  • Loose Wet

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

    These likely won’t be your normal loose wet avalanches, and you may need to treat them differently. We know the warm and sunny weather over the next two days will cause natural loose wet slides. The question is, when will the big and scary ones occur? We expect plenty of relatively small avalanches, on very steep sunny slopes, that don’t travel too far downhill Wednesday. When you see piles of new rollerballs or teardrop shaped debris, seek out shadier terrain away from steep sunny areas. However, if you notice these slides are entraining snow, growing large enough to bury you, or gouging into older layers, it’s time to get out of the way.  Avoid places where avalanches can start, run, and stop. So, the best way to manage your uncertainty is to choose terrain that allows you to easily identify and travel around avalanche paths if necessary. 

    Along with loose wet slides, this warm weather could bring other avalanches from sensitive cornices and even slabs. With two very warm and sunny days, all of these avalanches issues will at some point peak.

    (2/4/2022)

    Example: Natural loose wet avalanche occurring on steep sunny slopes earlier this winter. 

    Photo: Public Observation

  • Wind Slabs

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

    This was a big storm and even though it's over, you may still trigger slab avalanches in the dry snow. You’ll most likely need to manage this problem in the morning and on shaded aspects. Given the strong and gusty nature of the winds, don’t be surprised if you find wind-loaded snow in some unusual spots like well below ridgelines, along the sides of gullies, and even in the trees. Look for textured surfaces, sharp drifts, and fresh cornices to anticipate where wind slabs could linger. With so much new snow, if you trigger one of these avalanches it could easily be big enough to bury and kill you. 

    As the sun and temperatures start to affect the dry snow, it's hard to say how these wind slabs could react. Don’t assume just because it’s warmed up that this problem has been put to bed. Give steep wind-loaded features a wide berth.

    (4/2/2022) Example: Look for clues to help anticipate and avoid wind-loaded terrain.  Photo: Dallas Glass

Avalanche Discussion

Wednesday has the potential to be a very unusual day with such a rapid change in the snowpack. We have a significant amount of uncertainty about how this day will play out. Don’t box yourself in by choosing routes that require you to travel through avalanche terrain to exit. As the warm temperatures increase Thursday, our uncertainty grows and so does the potential for larger and more deadly avalanches. 

As of Tuesday afternoon (5 pm) Snoqualmie had received around a foot of snow at pass level with more than 3 feet at the top of Alpental. Very strong and gusty wind persisted throughout the two-day storm. This snow sits on the Early April Crust. You can use this prominent snowpack marker to help measure new snow depths and to focus your observations above this layer. We don’t anticipate slides involving deeper snow layers at this time.

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