Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

A few inches of new snow and stronger SW winds should add to the patchwork of wind-loaded terrain. These slabs will be bigger and more dangerous on the volcanoes and at upper elevations. Be leery of pillow-like drifts in steeper terrain, especially above rocks and cliffs.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Several days of stronger winds from a variety of directions left its mark on the snowpack. You may find old, firm wind slabs, shallower recent drifts, and actively forming pillows. Since Friday,  at least 12 unintentional avalanches have been triggered across the WA Cascades. The most recent occurred on Monday near Crystal Mt. Many were very close calls, including people being caught and carried. While wind slabs are common, this many reported avalanches are not. It may speak to the unusual nature of the recent wind loading patterns. 

    Blowing snow and fresh drifts will highlight newly forming slabs that should be easy to spot and avoid. However, you’ll also need to look out for deeper older wind-loaded areas. Scoured slopes and larger wind features can help you find these spots. While older wind slabs have likely started to heal, they may still fail on unsupported slopes or where they sit on weak facets.

    (2/19/2024)

    This graph shows the general locations of recent natural and human triggered wind slab avalanches since 2/15. 

    Photo: Northwest Avalanche Center

Avalanche Discussion

This rather persistent weather pattern continues to maintain nearly identical avalanche conditions day to day. Precipitation favors the volcanos. With more snow to blow around, that’s where you’ll find the biggest avalanches and greatest danger. Closer to the crest, you’ll likely experience lower hazard. 

Crusts formed on many southerly slopes during periods of sunshine on Sunday and Monday. In some places, they are thick but breakable; in others, they are barely noticeable. These firmer surfaces will help limit any wet avalanche concerns if the sun appears on Tuesday. If the skies start to break, expect piles of rollerballs and maybe a tiny wet loose slide from whatever new snow fell in the morning hours.

The upper snowpack consists of layers of settled snow, crusts, and facets over the Early February Crust (EFC), often 12-30 inches (30-75cm) below the surface. The exact depths and layering depend on aspect, elevation, and exposure to recent winds. A layer of facets has been consistently identified above the EFC at Crystal, Paradise, and White Pass. So far, we haven’t confirmed any avalanches on these weak grains. However, elsewhere in the region, a few recent wind slabs are suspected to have failed on this layer. Monday's avalanche near Crystal adds to this list. At the moment, the same place you may trigger an avalanche on facets is the same as the older wind slabs. If one of these slides releases it could fail above you or break widely. 

The other notable theme from recent observations is the wind sculpting of the snowpack. Expect scoured slopes and large irregular wind features.

Regions covered