Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

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

You can still easily trigger avalanches in wind drifted snow on Friday. Strong winds built stiff pillow-like slabs in open terrain at all elevations. Watch for signs of instability, such as cracks shooting away from your equipment, and avoid steep slopes where you find "fat" looking, textured drifts of snow. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2

    The recent strong winds sustained above 20mph for over 7hrs on Thursday and drifted snow into wind slabs even at lower elevations. Winds are forecasted to taper into the light to moderate range on Friday, but you can still expect to find reactive wind slabs on steep wind-loaded slopes and terrain features. You will likely need to steer around these wind slabs in steep open terrain at lower elevations, but avoiding these wind slabs in alpine terrain will be especially challenging. The most likely places to trigger wind slabs will be steep slopes below ridges, steep convex rolls, and the base of cliffs. Feel for stiff over soft snow layering and look for signs of cracking or collapsing to identify and avoid areas of unstable wind-drifted snow. Sheltered, low-angle slopes will be the best option to reduce to likelihood of triggering an avalanche. 

    (2/28/2023)

    These pillow like drifts below ridges are prime locations to trigger a wind slab. 

    Photo: Katie Warren

Avalanche Discussion

New snow accumulated on various surfaces, including slick crusts on southerly slopes and weak snow on northerly aspects. Therefore, you could find small storm slabs on steep slopes in sheltered areas. You can use inconsequential test slopes and quick hand pits to observe how the new snow reacts. Avoid steep terrain if you find the new snow sliding easily or test slopes producing mini avalanches. 

A generally strong snowpack exists throughout the East South, and the recent storms have been improving winter recreation opportunities significantly. However, the recent snow has piled up on various crusts. While we have not seen any avalanche activity on deeper, older snow layers, we are tracking these interfaces with the additional loading events.

I traveled into the Ahtanum Meadows area on Tuesday. Generally, I found 7-12 inches of new snow and excellent riding conditions. Snowpack test yielded unremarkable results. However, I did observe some weak snow below the Valentine's Crust, about 20 inches below the snow surface. You can check out my observation here for more details. Before the storm cycle on the 25th, Joe Dellaporta traveled into the American Ridge area near Bumping Lake and observed slick surfaces at lower elevations, dry faceting snow at upper elevations in the shade, and a thin sun crust on slopes with a southern tilt (observation). 

Thanks for the recent observations!

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