Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Another day of hot and sunny weather will result in wet avalanche activity at Snoqualmie Pass on Tuesday. The timing and location of these slides are impossible to predict, so make travel plans that put plenty of space between you and potential avalanche terrain. 

Avalanche problems

  • Loose Wet

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

    Continue to minimize your time in and below avalanche terrain as our heat wave continues on Tuesday. You'll likely encounter some form of wet avalanche if you're in the mountains. Whether that slide is loose, a cornice fall, glide,  or snow shedding from rocks is difficult to predict. Most avalanche activity should be loose and confined to the surface snow. However, a few of these may gouge down into older snow, growing large in the process. Of course, those shed-type slides could be the more dangerous and are almost impossible to predict.

    (3/16/2024)

    Wet Avalanches have been commonplace around the Pass over the last 6 days. Expect this to continue until the surface freezes.

    Photo: Charlie Hagedorn (Image CC-BY-NC-SA 4.0)

  • Glide Cracks

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2

    As alluded to above, shed-style avalanches are likely the more dangerous issue you'll need to manage on Tuesday. They're definitely the hardest to predict. A handful of these avalanches failed over the weekend, and as the hot weather continues, it wouldn't be surprising to see more. Whether glides, cornice collapses, or blocks of snow shedding from rocks, these large and unpredictable slides could occur at an hour of the day. This isn't the type of avalanche you trigger; it's the kind you avoid. Pay close attention to the terrain above you. Choose routes that help limit time traveling below crevasse-like cracks, looming cornices, or snow-covered faces.

    (3/17/2024)

    This glide avalanche released sometime during the night. Rockface, Alpental.

    Photo: Alpental Patrol

Avalanche Discussion

The warm and sunny weather seems like a fitting way to celebrate the first day of spring. Unfortunately, it brings with it dangerous avalanche conditions for the 6th day in a row. This type of wet avalanche cycle is the most challenging situation we forecast. There is no simple observation to let you know the scales are tipping, and often, the danger remains elevated for days. All of these factors make managing these conditions very difficult for backcountry travelers. Avoidance becomes the primary tool. 

Multiple nights above freezing, daytime temperatures soaring into the 50s and 60s, and little wind have resulted in a multi-day wet avalanche cycle. Over this warm spell, avalanche activity has waxed and waned, peaking at different times in different locations. The avalanche character has shifted throughout this period as well. Rollerballs and pinwheels, wet loose avalanches, slabs, glides, and cornice collapses have all been reported during this warm-up.

Two notable slides occurred on Saturday night at Alpental. A glide released on Rockface, and a cornice failed above Shot 6, entraining snow on the slope below. These are precisely the types of spring-shedding avalanches that are impossible to predict when a cold and layered snowpack gets thrown in the oven for the first time each spring. 

Temperature inversions may result in a firm surface crust at lower elevations in the morning, limiting activity. Keep an eye on the terrain above you - it will already be baking in the sunshine and will be more prone to avalanche activity. 

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