Avalanche forecast

East Slopes Central

Northwest Avalanche Center
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Avalanche danger

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

You will be able to trigger an avalanche on Monday as a storm impacts the region with new snowfall and very strong winds. Anticipate avalanche hazard rising throughout the day as the wind rapidly transports snow and builds fresh slabs.  Travel safely by seeking wind-sheltered terrain, giving cornices wide berth, and avoiding lee slopes over 30 degrees.

Avalanche problems

  • Wind Slabs

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

    Strong winds will rapidly form fresh and sensitive wind slabs which you will be able to trigger. Monday's storm should impact the region in the morning hours so expect to find wind slabs beginning to develop by the time you leave the trailhead. The likelihood of triggering a wind slab and the size of a potential wind slab will continue to increase through the day and as you move higher into more wind affected terrain. As always, use blowing snow and cornice formation as visual clues where slabs may be forming. Hollow sounding and firm or textured snow are other clues that wind transport is building slabs. The winds are forecast to be strong enough that slabs may develop further downslope than normal so be alert for cross-loaded terrain features and midslope slab formation. 

Avalanche Discussion

Stable avalanche conditions and fair weather have been the norm for a few days now. That changes Monday as a cold front brings strong winds and new snow to the region. Snowpack height and coverage varies significantly in the East Central zone. Areas near the cascade crest have a substantial headstart over the snowpack at low elevations and near Highway 97. Monday's storm will mimic this pattern keeping the more eastern peaks relatively dry while the best chance for significant new snow is close to the crest. Regardless of where you are in the East Central zone, the wind will be a major player Monday building fresh and sensitive wind slabs. 

At upper elevations, surface conditions are generally firm and wind-affected making for a good sliding surface as wind slabs form. Cornices have grown in the past couple of weeks and will continue to develop quickly as strong winds and new snow arrive Monday. At sheltered locations and on shady slopes weak snow surfaces are likely. NWAC forecaster Matt Primomo found widespread surface hoar preserved in the Teanaway mountains on all aspects (including solar aspects) above 5000'. This echos findings from nearby forecast zones. This could be a potentially reactive layer, especially where wind slabs form above it. 

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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