Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Over two feet of snow fell since Saturday in the West Central Zone. It is likely that human-triggered avalanches can occur on steep slopes, especially in areas more affected by the wind. Pay attention to surface clues such as cracking and stiffer snow surfaces, and avoid steep slopes in areas where you encounter these conditions.

Avalanche problems

  • Storm Slabs

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

    Human triggered storm slab and loose dry avalanches occurred in neighboring zones on Sunday. Natural loose dry avalanches happened during the storm as well.   Minimal information is known about the storm snow layers in the West Central Zone, but with information we do know, you could still trigger avalanches breaking in these layers. In the Stevens Pass Zone avalanches occurred in the top foot, generally in non wind-affected layers, but in the West North Zone only wind-loaded slopes easily reacted to a human trigger. At upper elevations where terrain is more wind-affected, you may find it easier to trigger larger avalanches. The wind slabs may also be covered with non-wind affected snow, so if you travel up high make sure to investigate a few feet down for weak interfaces before committing to a slope. 

    Pay attention to clues such as cracking as you travel. Use small test slopes to see whether shallower layers of snow easily break off. Look for signs of wind loading such as textured surfaces, pillow-like layers or firmer feeling snow. When you encounter any of these characteristics, avoid traveling on nearby steep slopes. 

    (2/20/2022) A skier triggered slab avalanche which occurred Sunday in the West North zone. This was an obviously wind-loaded rocky outcropping. Approximately 18" deep, 150ft wid. N, 5100ft. Photo: Pete Durr, USFS Backcountry Ranger 

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1.5–2.5

    Lingering concerns with the persistent weak layer exist now that another two+ feet of snow loaded slopes. In upper elevation areas where this concern exists the new snow could be drifted into much thicker, heavier deposits.  An avalanche hasn’t been reported on this layer in over a week, but the new snow (weight) in the last 48hrs and a human trigger on top could tip the scales and we might see avalanches on this layer. It's buried 3 or more feet below the surface on upper elevation northerly aspects. Traveling onto upper elevation northerly slopes on steep terrain with the recent snow load might give you a small chance of being caught in an even larger avalanche. This is a low probability, high consequence scenario, and valuable to consider before heading out on these slopes Monday. 

Avalanche Discussion

Sun breaks are expected Monday, and small wet loose avalanches might occur on south-facing slopes. Pay attention to sky cover, and if the sun starts shining through, you may see rollerballs or small wet loose avalanches running in the new snow- especially from steep, rocky areas. Avoid traveling through these areas if you encounter snow naturally running on these steep, south-facing slopes. 

Regions covered