Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Steer around wind-loaded slopes where you find 6" or more of drifted snow above the old snow interface or crust. Below 4500 ft we expect limited hazard with only a few inches of dry snow above a refreezing crust. If you travel very close to the West South zone where more snow piled up, consider basing your travel decisions on the adjacent zone forecast.

Avalanche problems

  • Wind Slabs

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

    If you travel in the immediate lee of the Cascade Crest, your danger might be more in line with CONSIDERABLE and you should consult this observation detailing widely propagating large slabs in wind-loaded terrain on Tuesday in the White Pass backcountry.

    For the remainder of the zone, we're expecting 2-6" of wind-drifted snow in the East South zone. Moderate SW and W winds with strong gusts will redistribute that snow into 6-12" drifts near and above treeline, creating potential for you to trigger D1.5 avalanches large enough to ruin your day. Look for the old snow interface. These slabs may rest on older wind-affected surfaces, temperature crusts, refreezing rain crusts (below 4500 ft), or potentially weaker surfaces on higher elevation or shaded aspects. Expect these slabs to run farther than you expect if they rest above weaker surfaces or crusts. Heed the cautionary signs of shooting cracks, firm over weak snow layering, or whumphs as you travel. And reduce your terrain selection as the average snow depth increases. Expect to steer around drifted lense-shaped pillows in typical avalanche start zones or on mid-slope convexities. If you find the average depth over 6" of snow, the danger may be more in line with considerable and you should avoid all potentially wind-loaded slopes steeper than 35 degrees.

    Example: Very small windslab beneath a cornice. These are the types of wind-loaded slopes you will want to steer around on Wednesday.

    Photo: Katie Warren

Avalanche Discussion

Tuesday's storm will be the largest accumulation event since the wet MLK storm, but it probably hasn't delivered the deep powder conditions we were anticipating. The good news is that the avalanche danger will be easier to manage than we expected. 

Expect plenty of sunshine on Wednesday to impact the low-density snow that falls Tuesday night. Eventually, the sunshine will overcome the cold temperatures and you can expect rollerballs to be followed by wet loose avalanches entraining the surface snow. These avalanches will be most consequential where they can push you over a cliff or into a gulley.

If you get out into the East-South, please let us know by submitting an observation!

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