Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Wet avalanches will likely be difficult to predict, sporadic, and larger as spoor overnight refreezes continue. Areas lacking a supportable crust will be fodder for wet avalanche entrainment. Keep an eye on your travel route and another on the slopes above you.

Avalanche problems

  • Loose Wet

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

    As the wet avalanche cycle continues, the avalanche size distribution changes. The larger, less predictable, and scarier type of wet loose slide should be your focus after several nights without a good refreeze. These avalanches occur in more isolated areas. You will primarily see them release naturally near and below cliffs on E-S-W aspects, but they start to entrain onto N aspects if the snow becomes heavy and wet. Travel early and reduce your exposure to larger terrain features once the crusts break down.

    Some aspects are further along in their spring transition and are trending toward homogeneity. In these areas, you may trigger the smaller and more predictable wet loose avalanches once the surface crust softens and the wet snow becomes deeper than your ankle. When you find wet, saturated snow, head to more shaded aspects or lower-angled slopes. These avalanches are most likely in areas receiving direct sunshine.

    During longer warm periods such as this one, shed-style avalanches (cornice falls, glides, and wet slabs) also could occur.  The longer a warm period extends, the more higher the uncertainty grows. And we're in the late stages of this one. Meltwater continues to increase in the snowpack, lubricating bedrock slabs or pooling on crust interfaces. These types of avalanches can release any time of day. Manage your overhead hazard by minimizing or eliminating any time you spend on or under snow-covered rocky faces and looming cornices.

    Wet loose slides from Saturday. (3/30/2024) Photo: Lauren Walker

Avalanche Discussion

Preliminary Report: NWAC is saddened to report an avalanche fatality as a result of a cornice fall on Mount St. Helens. On Friday, March 29, 2024, a snowboarder summited the peak. While standing near the top, he triggered a cornice and fell into the crater triggering a large slab avalanche on the slope below. NWAC is working with Skamania Co Sheriff’s office and SAR to compile a report. Our deepest condolences to the family, friends, and community.

Discussion:

NWAC forecasters in the White Pass backcountry encountered softening snow on the southern half of the compass, while northerly aspects retained cold, dry snow above around 6000 ft.

We're in the final 24 hours of spring warmup. Tuesday could be the warmest day yet and you don't want to expose yourself to surprises in this transitional regime. This is a good time not to limit your exposure to consequential slopes as superficial crusts break down once again. Activity can wax and wane, and avalanche activity could increase with little or no warning once snow surfaces soften, melt, and become gloppy. 

Although we expect wind slab instabilities are settling quickly in the heat, you may still find cold dry snow and even a few wind-loaded pockets on upper elevation northerly aspects. A snowboarder in the Crytal backcountry triggered one such avalanche on Sunday. These slabs should be limited to the upper extent of our forecast region but may speak to conditions above it, particularly on the volcanoes.  

The weather may feel like spring, but the snowpack has yet to transition from its winter-like state on many slopes. Under the surficial spring transition lie colder, drier layers and the potential for more surprises. Travelers over the weekend triggered numerous avalanches; some were caught, a few were carried and buried, and one was killed. 

During this warm-up, we’re primarily worried about the snow over the 3/21 crust. On southerly aspects, the entire upper snowpack may just be melt forms at this point. In other locations, you should find this prominent layer 1-2 ft below the surface. 

Prepare for rapidly cooling temperatures and stormier conditions that could surprise you if you're out in the backcountry Tuesday night.

Regions covered