Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Westerly winds will continue to drift snow into stiff slabs. You may be able to trigger small avalanches in steep rocky terrain near high elevation ridges. Even these small avalanches can be dangerous in terrain with cliffs and exposed rocks. Look for actively blowing or drifting snow and steer around steep terrain with stiff pillows of snow that feel or sound hollow. 

Avalanche problems

  • Wind Slabs

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

    Moderate winds may continue to build slabs of wind drifted snow. Steep, rocky terrain at the highest elevations is the most likely place to trigger these avalanches. Wind blown snow collects at the base of cliffs and on slopes below ridges. Look for actively blowing snow at ridgelines and use visual clues such as cornices and wind drifts to identify likely wind loaded areas. As you approach wind-exposed alpine terrain, use your probe to feel for stiff snow over soft snow. We expect most of these avalanches to be small, but they could also take you for a ride through rocks or over a cliff. 

    I was out near Clover Flats on Friday, and while I could identify weak snow layers near the base of the snowpack. Areas with blowing snow actively loading slopes may increase the pressure on these weak snow layers. These weak layers contribute to the increased avalanche danger in the East Central Zone. While I did not find these layers to be as touchy as conditions in East Central, this is our only data point, and other locations may have more dangerous conditions. An avalanche on this layer could be quite large and run on the ground. Make sure to listen and feel for signs of instability, such as large collapses or shooting cracks. These are sure signs you should stick to low angle routes. Even without these loud signals of instability, it is worthwhile to dig down and identify any weak, sugary snow in the snowpack before committing to new steep terrain.

    (12/3/2022) Example of drifting snow over a ridge. This wind-blown snow likely collected near the base of the cliffs and rocks seen in the foreground.

    Photo: Dallas Glass

Avalanche Discussion

I was out enjoying some early season riding conditions near Darland Mountain on Friday. Grooming operations have yet to begin in Ahtanum State Forest, but travel on the roads was smooth. While coverage is much better, it's still early season, so expect rocks and bushes to be just under the surface. With so many things to hit, I did not venture far from established roads.About 10 inches of snow exists at the trailhead, and the recent storm snow from 11/29 is the entirety of the snowpack until you travel above 5600ft. I found around 3 feet of snow at 6250ft in the sheltered terrain at Clover Flats. The upper snowpack consists of primarily low density storm snow. The base of the snowpack is a mixed bag of strong crusts and increasingly dense snow. At the base of the snowpack, I identified weak, sugary snow. This is the same layer that is causing persistent slab problems in the East Central zone. At this site, the layering did not appear as much of a problem, but we're still suspect of higher elevation terrain especially facing northwest through northeast. 

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