Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Triggering fresh shallow wind slabs could be what it takes to trigger a larger, more surprising avalanche. Signs of instability are becoming less common, but the consequences of these large avalanches should still shape your travel plans. Continue to avoid all steep open slopes greater than 30 degrees, especially where new snow has drifted into slabs. 

Avalanche problems

  • Persistent Slabs

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

    Light accumulations of new snow won’t likely tip the scales for this persistent slab problem. However, it will likely create a fresh batch of shallow reactive wind slabs in exposed terrain that could step down to persistent weak layers and become a much larger avalanche if triggered. 

    The likelihood of triggering one of these large avalanches that break 1-3 feet deep on buried surface hoar or facets above the 2/7 crust has gradually decreased this past week. Our last known avalanche that failed on this persistent weak layer occurred on 2/28 on Darland Mountain (observation here). 

    We’re getting to a point where you may or may not receive any signs of instability before triggering a large, potentially unsurvivable avalanche. Just because there are tracks on a slope, it doesn't mean it's safe. The best way you can reduce your exposure to this tricky problem is to avoid steep open slopes greater than 30 degrees, especially where the wind has formed deeper drifts, such as beneath ridgelines or in rocky terrain. 

    (2/28/2026)

    A large, machine-triggered persistent slab avalanche on 2/28.

    HS-AMu-R2-D2-O, NE, 6700'

  • Loose Wet

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

    Sunbreaks and clearing will become increasingly likely as the day progresses, especially in areas further east. The strong March sun may set the stage for wet snow instabilities on steep, sun-exposed slopes. Keep an eye out for rollerballs, pinwheels, and sticky snow surfaces as precursors for wet loose avalanches. 

    (2/6/2026)

    Wet loose avalanche activity on sun exposed slopes. This ridge is mostly east-southeast facing. This is the type of terrain where you could see activity. 

    Photo: Andy Harrington

Avalanche Discussion

The East South will be largely rain-shadowed by Wednesday’s system. Places like Darland Mountain and areas closer to Chinook Pass may squeeze out 2-3 inches of new snow with moderate winds, which should help form a new generation of shallow wind slabs in exposed terrain.

As mentioned earlier, we don’t expect this amount of water to have a great impact on the persistent slab reactivity in more sheltered terrain, but that may not be the case in more wind-exposed areas, where small wind slabs could be what it takes to activate a larger persistent slab. We suspect these new, shallow slabs could be reactive to a human or machine trigger, which is driving the considerable danger in higher terrain. 

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