Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

The wind may have drifted new snow into unstable slabs at upper elevations or on the volcanoes. Elsewhere, our snowpack is saturated, and unpredictable wet avalanches could still occur. Choose travel routes that limit your exposure to overhead hazards.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Dry snow problems should be back on your radar on Saturday. Expect the largest potential slabs to be located in wind-loaded areas, such as leeward ridgelines, the sides of gullies/chutes, or the base of cliffs. You can look for texturing of the surface, fresh cornices, or new pillow-like drifts to help identify wind-loaded features that you should avoid. Using uptrack tests, quick hand pits, or small test slopes can help determine how the new snow is bonding to the old surface or if midstorm instabilities are present. The new snow should be resting on a newly forming crust, which could act as a good bed surface.

    In wind-sheltered areas, expect the new storm snow to fail more like a loose slide.

    (3/28/2025)

    Obvious signs of wind transported snow on Friday near Crystal Mountain. 

    Photo: Dallas Glass

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    Under the new white blanket of snow will be the sleeping dragon. Our snowpack is saturated from this week's atmospheric river and unseasonably warm temperatures. We haven't had a good overnight freeze in almost a week. Wet avalanches are impossible to predict and can often occur long after the rain has stopped. Although cooling generally helps resolve these issues, the initial cool-down can sometimes trigger a final round of slab or glide activity. Glide cracks and precariously hanging cornices may get hidden beneath new snow, making them harder to assess. Your best mitigation tool will be to limit the amount of time you spend below large avalanche slopes, glide cracks, or sagging cornices where one of these low-likelihood, high-consequence slides could occur. If a wet avalanche releases, it will be without warning and will likely be unsurvivable. 

    (3/28/2025)

    Looking at the crown of a very large wet slab avalanche at Crystal Mountain. This crown is roughly 5 feet deep. [N, 6600ft,  WS-N-D3-O]

    Photo: Dallas Glass

Avalanche Discussion

The West South experienced a return to snow on Friday, resulting in some drifting and unstable pockets at upper elevations. The new snow was reportedly fairly heavy, with varying reports on how well it bonded to the underlying surface. Expect a few more inches by Saturday but with less wind. As temps bump up in the afternoon, you may see the new snow start to destabilize and kick off a round of shallow, wet loose slides. Although most of these should be relatively small, be leery of them gouging down into old snow layers in isolated locations. 

Which brings us to the elephant in the room. Our warm, wet, and weak snowpack. This week's atmospheric river and unseasonably hot temperatures did a number on our snowpack. Numerous very large natural and explosive-triggered avalanches were reported this week throughout the zone. On Friday, we received reports of another natural D3 sized avalanche that failed in recent days (post atmospheric river) near Crystal Mountain. That's the third one of these to occur. While we suspect these slides are unlikely to occur on Saturday, the fact that the surface is not yet "locked up" and frozen, and we've had a steady trickle of devastatingly large avalanches this week, means we can't entirely write this problem off yet. If you're out and about and find that the previously wet surface has firmed up into a boot-supportable crust, you may be able to let your guard down slightly. 

This week's wet avalanche cycle has littered the landscape with avalanche debris. Some may be hidden under the fresh snow. Holes, creeks, open water, and bare ground have all been exposed. Allow yourself extra time to navigate these hazards if you're playing out in the mountains on Saturday.

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