Avalanche forecast

East Slopes North

Northwest Avalanche Center
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Avalanche danger

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

Moderate and gusty winds will continue to drift recent snow into shallow slabs. Blowing snow and stiff drifts of snow are clues that can point you to the danger. Use caution on steep slopes below ridges where the wind has deposited fresh drifts.

Avalanche problems

  • Wind Slabs

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

    At the Cascade crest, 4-5 inches of new snow will have accumulated by Saturday morning. This will add to the soft snow available for transport by the gusty winds. Expect new wind slabs along exposed ridges and at the base of cliffs. Avalanches in these new slabs should be small. If you see any cracking or recent avalanches, stay off of nearby steep, wind-loaded slopes.

    You may be able to trigger avalanches in wind-sheltered terrain and wind slab avalanches could be easily triggered where the new snow has been deposited on a firm crust (southerly facing) or weak facets and surface hoar (shaded slopes). You can use simple tests like hand shears, test slopes, and tilt tests to evaluate the bond of new snow layers. Look for snow that breaks easily and cleanly at the new/old interface. You may find large, angular snow grains where surface hoar and facets were buried.

    (1/3/2025)

    A small skier triggered avalanche on a leeward slope on Delancey Ridge.

    Photo: Katie Warren

Avalanche Discussion

On Friday, observers reported 3.5" of new snow at the Hairpin Valley. Precipitation should end by Saturday morning but thick clouds and gusty winds could linger through the day. 

Just a few inches of new snow isn’t likely to wake up any of the older snowpack layers. We do have a new interface (1/10) to track. Prior to this storm, a crust developed on steeper southerly aspects, while other slopes remained soft and dry. Near-surface facets and spotty surface hoar were reported on many shaded slopes.

Several older layers still exist in the snowpack. Near the Cascade crest, the most consistent has been the 1/1 interface where surface hoar was buried by 4-6 inches (10-15cm). Snowpack tests have been inconsistent on the layer. While we generally don’t expect this storm to change that, you can’t write off an isolated slab failing on this interface. 

On Thursday, an NWAC forecaster on Sweetgrass Butte found a generally strong and well-settled snowpack with widespread facets and some surface hoar on the surface of all but southeast through southwest aspects. An older weak layer of facets, 10" below the surface, produced sudden test results but didn't propagate in large columns. Similar to the Jan 1st buried surface hoar, found elsewhere, This could be a layer to watch on leeward, loaded slopes. 

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