Bollettino valanghe

West Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

Thu
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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In sintesi

A new load of snow is increasing avalanche danger in the zone. It's likely you can trigger avalanches in the new snow layer, and there's a chance they could step down to produce even larger avalanches in deeper underlying weak layers. Stick to lower-angle, sheltered terrain on Wednesday, and if you see any large natural avalanches, steer clear of areas beneath large open slopes as well. 

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    It's likely that you could trigger a large slab avalanche in the new snow that falls Tuesday night and Wednesday. We suspect the most reactive layers will be in wind-loaded areas, but it may be hard to detect where wind-loaded slopes are- and up high, there's just a lot of incoming snow. This is a good day to steer around all steep terrain and stick to lower-angle, sheltered areas.

    By the end of the day, upper elevations in some areas of the zone could have around 18 inches of new snow. Expect greater danger in areas with more snow. Near the bottom of the mid elevation band, and possibly the top of the lower elevation band, there may be just enough snow for you to trigger a small avalanche.

    Even if you trigger smaller avalanches in the new layer, they could step down to a persistent layer on large, steep slopes and result in a very large, unsurvivable avalanche. 

    Example photo: Steep slopes could produce small and large avalanches in the new snow layer, like this one, on Wednesday. 

    Photo: Irene Henninger

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    2–3

    This is a day to travel cautiously and stick to conservative terrain. Although we have limited information from this zone, nearby zones have had several large and very large recent avalanches failing on persistent layers, and we suspect similar activity in this zone. New snow may further stress buried weak layers. Natural avalanches are possible. Consider that a smaller storm slab could step down into a much larger and more dangerous persistent slab avalanche.

     Classic warning signs like collapsing or cracking remain important, though deeper instabilities may give few clues. Favor lower-angle, less wind-loaded terrain on Wednesday. 

    (2/28/2026)

    Large, scary persistent slab avalanches that recently occurred in the neighboring West North zone. 

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Lower elevations received mostly rain during this storm- over an inch of it. Steep slopes that have a thick, wet layer of snow that you're sinking more than a few inches deep in could produce rollerballs or wet avalanches. There could also be natural avalanches in this layer of soft, wet snow. If you see natural avalanches, or you're sinking past your ankles in wet snow, stick to lower angle terrain and steer clear of the bottom of steep paths that an avalanche might run down to. 

    (3/3/2026)

    A natural wet loose avalanche that happened Tuesday in the Stevens Pass backcountry. N, 4500ft. More like this could happen on Wednesday. 

    Photo: Stevens Pass Ski Patrol

Avalanche Discussion

Forecasts call for about half an inch of water Tuesday night, and then similar amounts during the day. There could be more than a foot of snow at upper elevations.  Observations from neighboring zones show a weak and inconsistent snowpack. Buried surface hoar and crust/facet layers from early to mid-February have been found across the region, though test results vary. Some areas have produced recent avalanches on these layers while others remain quiet, so reviewing forecasts from nearby zones can help with trip planning.

A lack of recent avalanche activity doesn’t mean the problem is gone. Ongoing avalanches in parts of the region—and recent warming—suggest instability can still develop where these weak layers exist. The overall picture is variable and unpredictable: slopes that seem stable may still harbor deeper weaknesses. Careful terrain selection remains the most reliable way to manage risk, as large or very large avalanches are likely with this added layer of new snow. 

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