Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

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

It continues to be an active weather week and triggering an avalanche in exposed terrain steeper than 35 degrees is likely. Look for snow blowing around or overhanging masses that jut out over the side of a ridge to clue you into where wind-affected snow is. Signs of instability include long shooting cracks from your equipment and audible collapsing. If you see bits of snow rolling down on a sunny slope, a small wet snow avalanche could soon follow.

Avalanche problems

  • Wind Slabs

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

    The closer you are to the Cascade Crest and higher in elevation you travel, the more likely it will be to find both new and old wind slabs. The likelihood of triggering an avalanche is lower in areas further east, such as the Wenatchees. Older and deeper slabs formed on Thursday night will be less reactive, but triggering one could create an avalanche large enough to bury you.

    Wind slabs typically form just below ridgelines and in gully or chute-shaped terrain features. Wind speeds have been strong, so you could encounter wind-affected snow lower down on slopes than you might expect. Look for clear signs of wind transport: dune-like drifts, cornice formation, and blowing snow. As you move about the terrain and the snow begins to feel denser and look unevenly distributed, assume wind slabs probably lurk nearby. In addition to cracking and collapsing, recent natural slab avalanches are very good reasons to avoid exposed terrain steeper than 35 degrees.

    (3/18/2025)

    A small sledder triggered wind slab avalanche in the Salmon La Sac (East Central). SS-AMu-R1-D1-O

    Photo: Evan Pearson

  • Loose Wet

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

    With sun breaks in the morning/early afternoon and decreasing wind on Saturday, you could find some unstable wet snow. The typical initiation of wet loose avalanches involves rollerballs and pinwheels or chunks of snow falling from cliffs and trees. It's unlikely you'll encounter a wet snow avalanche at upper elevations, but not out of the question. If you're on a sunny slope and the snow is becoming sticky and moist, find lower angle or shadier slopes. 

    (3/21/2025)

    Rollerballs and wet loose debris below a steep slope at 4400ft. Tree bombs were also plentiful.

    Photo: Josh Lipkowitz

Avalanche Discussion

The Thursday and Friday storm delivered as promised, depositing 0.5-1.10" of SWE to the zone, favoring the Cascade Crest. With it came the forecasted winds. Observers reported reactive and touchy wind slabs on varied aspects in the neighboring East Central zone. Yet another windy storm will bring another 2-6" Friday night, favoring the Crest.

With each delivery of new snow in the last week, wind slabs of varying sizes and sensitivities have formed. There was a report of someone getting caught and carried in an avalanche for five consecutive days out of the last nine. All of this stands to serve as a good reminder that we must ease into terrain after stormy periods, regardless of the circumstances. As we go into the weekend, expect conditions to still be complex and potentially increasing in hazard when an atmospheric river event begins Saturday night.

Storm slab instabilities may exist closer to the Crest. If you plan on traveling in these western parts of the zone, approach steep, unsupported terrain with some suspicion. You can use a small test slope or simple hand pits to help you gauge the reactivity of the recent storm snow. Cracking and collapsing similarly indicate instability in new snow.

The zone lacked consistent snow coverage below 4500 ft prior to all this stormy weather. We don't have on the ground data on what the snowpack looks like now, but we don't expect there to be too much avalanche danger at lower elevations. Keep an eye out for hazards such as rocks and downed trees, which could be obscured by new snow.

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