Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

A surface crust should help keep wet avalanche danger in check early in the day. But if the sun comes out, it may not take long for that crust to break down and for the surface snow to get wet. If you start seeing roller balls, pinwheels, fresh wet avalanches, or find yourself sinking past your boot tops into mushy snow, it’s time to move to lower-angle terrain.

Avalanche problems

  • Loose Wet

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

    The likelihood of wet loose avalanches initiating on the surface is declining after several warm days and a much-anticipated overnight freeze. Still, the newly formed crust may not last long once it starts warming in the sun—especially below 5,000 feet. Beneath that crust lies plenty of mushy, wet snow, and any new wet loose slides could gouge into the weak snow below and grow in size as they descend. While we expect less wet avalanche activity than we’ve seen over the past couple of days, it’s still possible on steep, sunlit slopes.

    This particular flavor of wet avalanche is fairly straightforward to manage. Watch for the telltale signs mentioned in the bottom line and switch aspects if you see them. Remember that steep, rocky slopes above you may warm up faster than the snow you’re standing on. If the sun pops, limit your time beneath steep, sunlit terrain.

    At the highest elevations, a few inches of snow may have fallen overnight. If you make it up there, that snow could shed quickly once it’s warmed by the sun—but any resulting slides should remain small.

    As for the elephant deeper in the snowpack, this surface freeze won’t do much to change things down low. Deep wet slides, while unlikely, remain a high-consequence problem. Wet slabs, glide avalanches, cornice failures, and snow peeling off rock faces (“blob-a-lanches”) all remain on the table. These aren’t the kind of avalanches you’re likely to trigger yourself—but if one goes, it could be big and destructive. Managing this kind of uncertainty is personal. Acknowledge it, plan accordingly, and move quickly through avalanche paths to minimize your time in harm’s way.

    (4/9/2025)

    A large natural wet loose avalanche observed Wednesday in the Crystal Backcountry. This slide entrained significant amounts of snow as it descended, as can be seen in the sizeable debris pile.

    Photo: Andy Harrington

Avalanche Discussion

A quick system Thursday night brings a bit of liquid water, some wind, and not much else to the snowpack. The initial wave of this storm won’t do much to change the current avalanche conditions. A few tenths of an inch of rain pale in comparison to what the recent warmth and sunshine have already done to the surface snow. The bigger impact will come from the colder temperatures that follow. Nights will gradually cool through Sunday morning, helping to refreeze and stabilize the upper snowpack. That first freeze Thursday night may not be substantial—especially at lower elevations—but the lower-elevation snow has already been through a lot, and most of our concern there is from larger avalanches running down from above.

Expect Friday’s surface snow hazards to be very dependent on sunshine. If skies stay cloudy, wet loose activity will likely remain low. But if the sun comes out, you’ll still need to stay heads-up and manage your exposure. At the highest elevations—especially on the volcanoes where more snow may fall—you could encounter isolated dry snow instabilities like wind and storm slabs, as well as cold snow that's vulnerable to rapid warming in the sun. Also keep in mind the risk of a long sliding fall on steep, frozen slopes.

The snowpack is currently stuck in a slow, uneven transition toward spring. There’s free water moving within, some wet layers and interfaces, and plenty of snow that remains dry and wintry. It’s not fully frozen and it’s not fully transformed. Big wet slides are unlikely—but not entirely out of the question. Build a wide margin of safety into your day and approach each slope with an open mind.

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