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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Highlights

Wet snow avalanche concerns will be front and center as mild temperatures and potential sunshine follow a heavy wet snowstorm.  Loose wet avalanches may become large and dangerous on slopes where they gouge down to deeper layers.  Stay off of and away from steep open slopes at mid and upper elevations.

Avalanche problems

  • Loose Wet

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

    A mild Monday night will be followed by a warm Tuesday, one that will likely feature afternoon sunshine.  Following our heavy wet snowstorm Sunday night and Monday, the recent snowfall will be primed to move downhill in the form of loose wet avalanches.  It should be a downright dangerous day at mid and upper elevations where loose wet avalanches could easily entrain the top 1-2' of recent snow that has accumulated above 5000' over the last few days.  

    Tuesday is a day to minimize your exposure to large avalanche paths as slides may release naturally.  If the sun comes out in the afternoon, think about the strong late March sunshine affecting more aspects later in the day.  When plotting your travel route, you'll also need to consider your exposure to slopes with large overhanging cornices.  Cornices that weaken and fail can trigger large avalanches on the slopes below.  Make sure to give them a wide berth if traveling along ridgelines.  

    While avalanches are likely to be smaller at lower elevations, stay off of any steep slopes if you find yourself sinking into wet punchy snow deeper than your ankle and move to simpler terrain.  There are many terrain traps at lower elevations like open creeks, trees, rocks, etc that you don't want a deceptively powerful wet snow avalanche to knock you into. 

    (3/3/2022)

    Loose wet avalanches may become large and dangerous on Tuesday like the example in this recent photo.  Think about the terrain you're connected to at all elevations.

     

    Photo: Alpental Ski Patrol

Avalanche Discussion

The Snoqualmie Pass area received about 8-14" of snow Sunday night through mid-day Monday,  with the higher totals recorded above 5000'.   A slow warming trend occurred throughout the storm and produced a natural avalanche cycle.   Avalanche professionals noted a loose wet avalanche cycle below 4000' as temperatures warmed Monday.  They also observed natural storm slab avalanches releasing on steep slopes at higher elevations.  Many were small, but a few larger slab avalanches occurred. 

While we're mostly concerned about avalanches involving the most recent snow, it's worth keeping in mind this a test of deeper weaker interfaces in the snowpack.  A layer of weak facets sits over a very thick and stout crust on NW-NE aspects near and above treelines. This layer is likely 3 ft or more deep in the Snoqualmie Pass zone.  So far, only one small avalanche has been reported on this layer in the zone.  That said, until we lock up the snowpack, it would be wise to factor in the possibility of a very large avalanche releasing down to this interface with a large trigger like cornice fall.  

At lower elevations travel continues to be difficult. Wet sticky snow, firm rough surfaces, open creeks, and frozen piles avalanches could all make travel challenging.

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