Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

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

You'll need to manage a mix of wet and dry avalanche problems on Friday. Slabs will be more likely as you ascend in elevation on unsupported slopes, convex features, or in wind-loaded terrain. While some low-elevation terrain does not have the consistent snow cover to allow for avalanches, enough places do that it should be on your radar.

Avalanche problems

  • Storm Slabs

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

    As you ascend in elevation, you'll encounter drier snow and the potential for slab avalanches. They'll be more likely on unsupported slopes, convex rollovers, or in wind-loaded terrain such as confined chutes or the base of cliffs. Slabs could be possible at elevations with moist snow but may be more stubborn. Use quick hand pits to look for potential layers of concern. Uptrack tests and small test slopes can help you gauge how the snow reacts to your weight as a traveler. Visual clues like large drifts, textured surfaces, or "fat pillows" can help you identify loaded features.  Avoid steep features over 35 degrees if you see any signs of instability.

    (3/27/2024)

    A storm slab avalanche that failed on a steep convex slope in the neighboring West South zone.

    Photo: Dallas Glass

  • Loose Wet

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

    Daytime warming, sun breaks, or rain showers could destabilize the snow surface and create the conditions for wet avalanches. Heavy wet snow already exists in many areas and is waiting for something to help push it downhill. Once these slides get moving, they can grow large and powerful as they descend and gather snow. In some areas, they could even trigger slabs. If the snow surface is wet and weak and you see new rollerballs, pinwheels, or snow shedding from trees and rocks, head for lower-angled terrain.

    In isolated locations, larger, more unpredictable shed-style avalanches could occur. Keep an eye on the terrain above you, and don't linger where you see precariously hanging blocks of snow.

    (3/28/2024)

    Snow pouring off Big Four into lower elevation terrain where you may not be thinking about avalanches.

    Photo: Nick

Avalanche Discussion

Our springtime storm cycle continued on Thursday with another round of snowy but warm weather. A public observation from the Mountain Loop relayed widespread wet avalanche activity at low to mid-elevations and older deeper crowns in high-elevation northerly terrain.

In the neighboring West North zone,  Baker Patrol reported slabs as much as 1 foot deep in this week's snow. Over at Snoqualmie Pass, Alpental Pro Patrol reported 4-6" slabs during their morning mitigation work and wet loose avalanches at lower elevations as daytime warming destabilized the snowpack. A chunk of snow failed on one of their glide slopes, triggering a D1.5 wet loose avalanche on the slope below. 

That pretty much sums up conditions on the west side of the crest right now. Higher elevations are holding onto dry snow, while lower elevations are wet and punchy. There's a transition zone in the middle where you'll likely find a mix of the two problems and moist snow. Isolated shed-style avalanches could occur at any point as the mountains shed their winter coat. Expect similar conditions on Friday but with a higher chance for sun breaks and a downtrend in wind and precipitation amounts.

Be ready for rapid changes in weather and snow stability as we head into the heart of spring. Intense storms can give way to sun and microwave-like warming in a matter of minutes - and then turn back to snow showers by the afternoon. Dry snow avalanche problems can quickly turn into wet snow avalanche problems, or you might see both simultaneously on slopes with different aspects. Low elevations have less snow than average after repeated rain and warming events throughout the winter. 

Regions covered