Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Several avalanche professionals reported wind-loaded slopes all across the West South zone following Tuesday’s east wind event. Be leery of these firmer pillow-like drifts as you travel. Given the recent direction of the wind, you may find them in some unusual spots.

Avalanche problems

  • Wind Slabs

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

    Winds slabs are pretty common in the West South zone, but two things make this problem different: easterly winds and extremely cold temperatures. East winds load slopes that are frequently scoured by prevailing wind directions. So, you may find drifted snow in some unusual locations. As a result, you’ll want to be on the lookout for clues like textured surfaces, scoured slopes, and sharp drifts that point towards wind-loaded areas. If you see firmer pillow-like slabs, consider traveling around them. These possible avalanches should be relatively small and thin, but could still hurt you, especially in rocky terrain. Even though these slabs are a few days old, the very cold temperatures may prevent them from healing. So, don’t write them off just yet. Continue to be leery of any wind-loaded slope.

    (2/23/2022) Wind drifting along ridge tops on east slopes/faces. Photo: NPS Rainier Rangers

Avalanche Discussion

It looks like another frigid start to the day on Thursday around the West South zone. Very cold temperatures, mostly cloudy skies, and moderate winds could make it feel downright arctic in the morning. However, as the day goes on slightly warming temperatures, increasing sunshine, and lighter winds should make for a gorgeous day. The recent very cold weather has helped preserve the recent storm snow in most areas. Sunshine this week, did produce a thin crust on steep southerly slopes in some areas, but below the surface cold dry snow still exists. This surface crust and cold temperatures should limit any potential loose avalanche activity on Thursday to a few very small slides in the steepest terrain. 

This past weekend’s storm brought 10-20” of snow to areas around the zone, with the highest totals on the volcanoes. Below the new snow, what you will find depends entirely on the aspect. On slopes that receive direct sunshine, the storm fell on a very firm and thick spring-like surface that combines nearly all recent crusts into one strong block. On more northerly terrain, the snowpack contains a much drier, weaker, and layered structure. A thin weak crust was buried at the start of the storm on 2/19. While this layer can be hard to find in some areas, look 1-2” above the more prominent Valentine’s Day crust. In some locations, weak snow was found between these two layers, but so far no avalanches have been reported on these possible weak grains. For the moment, we’re keeping our eye on the Valentine’s Day-2/19 crusts and the snow around them.

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