Boletín de aludes

Stevens Pass

Northwest Avalanche Center
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Peligro de aludes

Tue
Alta montaña
3 · Notable
Límite del bosque
3 · Notable
Bajo el límite
2 · Moderado
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Desactualizado: este boletín caducó 6 months ago. Estás viendo condiciones pasadas, no el boletín vigente.

Lo esencial

A storm bringing fresh snow could overload our weak snowpack, and avalanches could be very easy to trigger or break in surprising ways.  Whumphing collapses and long shooting cracks are red flags to avoid steep open slopes and convex terrain features. Avalanches will be larger where the wind drifts snow deeper, so with these dangerous conditions, seek out sheltered, low-angle terrain.

Problemas de aludes

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Likely
    Tamaño
    1–2

    With a fresh snow load, avalanches may fail on buried weak layers, even in sheltered terrain. On sheltered slopes, these avalanches may act more like your average storm slab. However, in wind-loaded areas, they may break widely across terrain features or be triggered remotely. You'll want to steer clear of steep lee slopes near ridgelines, where these avalanches are likely to be much larger.

    Long shooting cracks, whumping collapses, or natural avalanches are key indicators of dangerous avalanche conditions. Small, steep test slopes or convex features can help gauge the reactivity of the upper snowpack. But given snowpack variability, be cautious about extrapolating your results too broadly.  Instead, seek out low-angle terrain protected from the wind while the snowpack adjusts to the new load, and we gain more information on the buried persistent weak layers.

    (2/21/2026)

    In the neighboring Snoqualmie Pass zone, an unintentionally triggered, widely propagating avalanche from 2/21. N, 5500ft.  It's unconfirmed, but this slide may have failed on older persistent grains. 

    Photo: NWAC

Avalanche Discussion

The most significant storm we've seen in a while is headed our way. While it isn't even a strong storm by PNW standards, it will still bring fresh snow and windy conditions along ridgelines. On an average snowpack, this might not result in many avalanches. But our snowpack is anything but average, and this additional load could be the tipping point for sensitive, large avalanches that fail on weak snow (2/13) buried earlier this month. We have some uncertainty about the extent of avalanches and how many we'll see occur in sheltered terrain, but it's a setup that warrants an abundance of caution. Assume widespread instability unless the snowpack proves otherwise. 

Observers are already reporting widespread avalanches in other zones. On the 20th, an observer in Stevens Pass sidecounty reported collapsing around 4,500ft. On shaded, less sun-exposed slopes, there's 8-12" of soft, dry snow with a layer of weak facets and surface hoar (February 13th) immediately above the uppermost, thin crust (February 8th). About 10-14" below the surface, you'll find a more stout, thicker crust that resulted from warm temperatures and rain in late January and early February. On sunny, southeast through southwest slopes, there are numerous recent crusts with less overlying weak snow. However, a small remotely triggered avalanche on the S aspect of Jove Peak suggests that persistent slab avalanches could be an issue on sunny aspects as well. Upper elevations will likely have a greater separation between crusts, with potentially more weak snow between them.On Tuesday, an NWAC forecaster outside the Stevens Pass ski area boundary found plenty of weak snow surrounding a couple of crusts in the upper snowpack. We have limited information from upper elevations, above 6,000ft. If you travel there, we'd love to have your observations!

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