Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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

Triggering an avalanche is possible in freshly wind-drifted snow at mid and upper elevations. Be on the lookout for steep terrain holding shallow but unstable slabs perched on slick crust or old, hard wind slabs below.

Avalanche problems

  • Wind Slabs

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

    Observers reported just enough new snow and wind to make a few fresh wind slabs near and above treeline. Expect more of the same Wednesday morning. New slabs will probably be spotty in distribution and small in size - but big enough to be a surprise if you get caught off guard. As usual small avalanches can have big consequences in extreme or otherwise consequential terrain. 

    If you trigger a slab avalanche it would likely be on leeward slopes just below ridgelines, or on terrain features like convex rollovers, gully walls, or around cliffs and rock outcroppings. Look for blowing snow, changes in snow consistency, or visual clues like wind-scoured ridgelines to identify areas of wind slab.

    Small wind loaded features at ridgeline can serve as test slopes to gauge the reactivity of fresh wind slabs.

     

Avalanche Discussion

While the rest of the Cascades saw little in the way of precipitation, West North managed to squeak out 0.2-0.3” of snow water equivalent at weather stations in the western half of the zone. This probably equals 2-4” of new snow - just enough to begin covering the sun crusts and wind eroded surfaces observed Sunday. Heather Meadows picked up just under 0.1” but it was still enough to produce a few inches of light new snow.

If the sun breaks out Wednesday you might see minor signs of instability like rollerballs or very small wet loose avalanches in areas that received new snow. Dry loose sluffs are still worth being aware of on the steepest slopes. Good riding conditions can still be found and a few inches of fresh will only make things better. 

Under the few inches of new snow, slick sun crust and debris from older wet avalanches top the snowpack on solar aspects. Near-surface faceting was observed in sheltered areas around Heather Meadows on Sunday and faceting around the MLK crust buried 1-3’ deep has been reported in adjacent zones. Neither surface nor crust faceting is currently an issue. On the other hand, they are layers to track going into fresh snowfall and loading at the end of the week.

Regions covered