Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Wet avalanches will take center stage as a springtime storm approaches on Monday.  Moist surfaces, rollerballs, or fan-shaped avalanche debris are all signs that you should head for simpler terrain. You might encounter wind-loaded pockets on the volcanoes or at higher elevations.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    This time of year, it doesn't take much for the surface to reach the threshold needed for wet avalanche activity. Recent snow could destabilize due to solar influence, rising temperatures, or wet precipitation. We could have all of those on Monday. Keep it simple - plan for wet avalanches wherever the snow surface is sticky and moist.

    Wet loose slides often start at a point near trees, rocks, or people and then fan out as they move downhill. You'll likely see other wet avalanche activity such as rollerballs, pinwheels. or snow shedding from rocky ledges whenever you encounter wet loose conditions. Make travel plans that limit your time spent on slopes over 35 degrees or areas with overhead hazards that could fail during periods of warm weather. 

    (4/6/2024)

    A wet loose avalanche triggered in the Crystal Mountain area over the weekend. Note how the sun can be seen through the thin clouds.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    At upper elevations, shallow slabs could exist in wind-loaded terrain, particularly on the volcanoes. Look for fresh drifts, textured surfaces, or new cornices to determine loading patterns. You can feel for changes in the depth of snow over the crust to help identify wind-loaded features to avoid. They'll be more common on leeward ridgelines, on convex features, or near rocky outcrops such as the base of cliffs or confined chutes. 

    (4/4/2024)

    Small cornices on a ridgeline in the Tatoosh Range. Deeper pockets of wind-drifted snow existed on the slopes below.

    Photo: Andy Harrington

Avalanche Discussion

Back and forth we go. That's springtime, baby. The upper snowpack started the weekend off cold but steadily transitioned toward warm and moist. Wet avalanche activity followed, with a handful of small slides reported. 

All reported activity was confined to the recent snow over the 4/2 melt-freeze crust. This easily identifiable interface can be found up to a foot below the surface. Temperatures and, thus, wet avalanche potential will slowly climb on Monday into Tuesday. Rain will start light but intensify on Monday night, possibly resulting in more shed-style avalanches. Snow clinging to rocky ledges, sagging cornices, or possibly glides are all concerns as the spring shed continues. This storm will focus on the northern half of the zone, particularly the Rainier area. If you're traveling on the southern volcanoes, take a peek at the Mt. Hood forecast to get a feel for conditions from our nearest neighbor. 

Lower elevations contain relatively low snow coverage. But where adequate snow exists, small avalanches are possible. More likely, you'll need to manage travel hazards. Open holes/creeks, shallowly buried rocks, and refrozen avalanche debris are more prevalent down low, but they litter the landscape at all elevations. Give yourself extra time and bring the tools required to travel safely.

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