Bulletin d’avalanche

West Slopes North

Northwest Avalanche Center
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Danger d’avalanche

Mon
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
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Périmé — ce bulletin a expiré 6 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Although chances are slim, a deep, very large, and unsurvivable avalanche could happen naturally or with a human trigger, similar to what occurred in the Baker backcountry Saturday afternoon. Especially as temperatures warm, avoid traveling beneath large, smooth slopes. South-facing crusts will quickly soften and become moist, and if rollerballs or small loose avalanches begin occurring, shift travel to cooler, shadier slopes.

Problèmes avalancheux

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    2–3

    A very large natural avalanche (observation) occurred in the Baker backcountry late afternoon Saturday. This may be the only one like it, but we really aren't sure, and it's too scary to ignore. These may increase in likelihood as temperatures increase into Sunday, and wetting occurs on slopes facing the sun, impacting shallower buried weaknesses that may continue to propagate into thicker areas. 

    Identify overhead hazards where you travel. Although the likelihood is low, you may want to consider steering clear of large, smooth, steep slopes and areas beneath them at upper and mid elevations, especially as the day warms. We don't expect large or very large avalanches at lower elevations, but larger avalanches may run down to these areas. 

     

    (2/28/2026)

    A very large natural avalanche that occurred in Video Peak in the Baker backcountry at 4:19pm on 2/28. This is the only one we've seen like this, but it's hard to ignore. 5500ft, N-NW, HS-N-D3-U

    Photo: Zack McGill - Cascade Mtn Ascents

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    Wet loose avalanches will be possible when crusts from Saturday break down and snow gets wet.  Avalanche size will vary with how much recent snow has accumulated—expect larger, more consequential slides in areas that picked up the most new snow. Size also depends on terrain, as steep, sustained fall-line slopes can produce more powerful avalanches. But even a small wet loose avalanche can pose a serious risk if it carries you over a cliff, into a creek, or through rocks or trees. Keep track of sunny slopes overhead as the day warms.

    (2/28/2026)

    Rollerballs on steep, sunny slopes midday Saturday. Expect more, possibly turning into wet loose avalanches on Sunday. 

    Photo: Julz Holder - Grounding Truth

Avalanche Discussion

Several small to large natural avalanches occurred in recent storm layers, mainly as natural avalanches early Friday morning. A few more occurred on Saturday. Folks were out in full force, both sledding and traveling under human power, and only a few human-triggered avalanches were reported. Some avalanches were small and isolated. You may still trigger slab avalanches in newer snow layers on Sunday, epsecially in wind loaded areas.  Cornices could start failing, triggering slab avalanches on underlying slopes with the warm temperatures we're seeing on Sunday as well. 

In the West North zone, avalanche activity has been limited and sporadic. Red flags like whumphing and shooting cracks have not been widespread, and persistent weak layers have been harder to find—though not impossible. This one large natural avalanche could be an indicator of more to come as temperatures warm up.  

Avalanche forecasts for large zones are often difficult to pin to a single danger rating, and Sunday may be especially challenging given the wide variation in new snow amounts, the potential for both slab and loose avalanches, and the uncertain distribution of persistent weak layers. Be prepared to find danger higher or lower depending on where you travel within the zone. Build flexibility into your plan so you can adjust based on what you find. With new evidence of very occasional large natural slab avalanches, this makes it even more tricky- you probably won't find signs of instability, but there's the tiny chance a very large avalanche could occur unexpectedly. 

 

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