Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
4 · High
Treeline
4 · High
Below
3 · Considerable
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Highlights

The brunt of the storm has passed, but snowfall, freezing rain, and strong winds will continue Friday. Very dangerous avalanche conditions linger at upper elevations. Avoid travel on or below slopes 30 degrees and steeper, especially where you find evidence of wind-drifted snow.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    2–3

    SNOTELs throughout the East South Zone report 1-2in of water equivalent translating to 2-3ft of new snow, and even more suspected in areas closer to the Cascade crest. All the new snow will easily be transported into thick and reactive drifts by strong S-SW winds. A natural avalanche cycle began Thursday during the heaviest precipitation rates, and will likely continue through Friday especially in wind-loaded, upper elevation areas. Avalanches could break several feet thick on a variety of new and old snow layers. The thickest and most reactive slabs will be found above treeline. Continue to avoid travel in areas avalanches can start, run, and stop.  

    (1/4/2022)

    Windy conditions during the recent storm have formed fresh cornices and loaded slopes near ridgelines. 

    Photo: Dallas Glass

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2

    The snow continues to pile up, with changing temperatures and chances for mixed precipitation. Large natural avalanches in new snow are likely at all elevations, even below treeline. These avalanches could even break widely across terrain features, or be triggered from a distance. Rain is even possible at the lowest elevations where avalanches may develop a wetter character. Only venture out during the storm if you are confident in your ability to identify and avoid avalanche terrain. 

    (1/4/2022)

    Expect storm slabs like these to be widespread and large. 

    Photo: Dallas Glass

Avalanche Discussion

The most significant storm and avalanche cycle so far this season is underway. These are unusual conditions with avalanche hazard even extending to lowland areas. Avalanches closed Highway 10 and Yakima Canyon Road Thursday, and landslides closed Highway 14. Many roof avalanches were reported throughout the region as well. Friday may be another good day to wait out the storm and let mother nature run its course.

The rapidly changing weather will create a mixed bag of unstable snow, all of which will likely produce avalanches large enough to bury or kill you. Precipitation types are hard to determine with this warm air overriding cold air pooled east of the Cascades. There is a chance of mixed precipitation and ice accumulation, creating a different but significant hazard for travel. And if warm air erodes the cold air pooled east of the Cascades, a change to rain may occur and create the potential for wet avalanches. 

While most observations have indicated a good bond between the upper snowpack and the Solstice crust, now buried 2-3 feet below the surface, some surprising avalanches in other zones have occurred on this layer. Including an explosive triggered slab that stepped down to this layer during avalanche mitigation work at Mission Ridge on Monday. These layers are the likely culprits in ongoing avalanche activity.

Regions covered