Avalanche forecast

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Northwest Avalanche Center
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Avalanche danger

Mon
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Highlights

Strong winds along with very light snowfall may create isolated wind slabs near and above treeline Sunday.  If freshly drifted snow at higher elevations is more widespread or deeper than forecast, use caution on slopes steeper than 35 degrees.  

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1

    A weather system moving through Sunday morning will kick up strong ridgeline winds but likely only produce 1-3" of snow near Washington Pass with lighter amounts further east.  If you find more than a few inches of new snow in wind-sheltered locations Sunday,  fresh wind slabs may have formed on lee slopes and be more widespread than anticipated near and above treeline.  Where you see overhanging cornices and fresh wind drifts, use caution on steep slopes with similar features.  Consider the consequences of a small avalanche near terrain traps like cliff bands.  

    Example of intense wind loading off a ridgeline.

Avalanche Discussion

From January 11th to 13th a major storm delivered heavy snow and even some rain at lower and mid-elevations to the region. The Harts Pass Snotel picked up about 2.7" of water over the event.  Very large and destructive avalanches ran through entire avalanche paths. The avalanche cycle occurred on the night of the 12th. Observers reported avalanches to at D3 in size (big enough to break mature timber and bury cars) including an avalanche that hit a closed portion of Highway 20, below Delancey Ridge. This avalanche ran over 3,000ft and formed debris piles that were 9 feet deep in places. 

More recently, winds, periods of sunshine, and milder temperatures have left a variety of snow surfaces throughout the terrain.  While the weather and avalanche cycle has quieted down, we still have a fair amount of uncertainty surrounding higher elevations where there have been fewer recent observations following last week's storm.  If you encounter areas with a firm and slick surface crust, use caution before crossing steep slopes. Either move to lower angled terrain or make sure you can self-arrest a fall. 

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources. Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

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