Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto last year. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Saturday will bring the third day of very warm temperatures and minimal freeze. Large, wet avalanches could run naturally, and you could encounter a range of other dangerous conditions. Sun and warm temperatures could open glide cracks and cause snow-covered rocks and cornices to fall.

Problemi valanghivi

  • Loose Wet

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

    Once surface crusts melt, directly sun-exposed slopes on southeast through southwest aspects could be wet and unsupportive.  Wet avalanches will be possible on more shaded terrain. Move to lower-angle slopes if you see rollerballs or fresh avalanches. Be aware of avalanches coming from overhead terrain. They may run naturally from above. 

    Consider the consequences of a large glide avalanche or cornice fall. While these may be less likely, the consequences could be severe. Avoid lingering underneath glide cracks, cliffs, or overhung cornices. These overhead hazards run naturally and could trigger an avalanche on slopes below.

    (2/24/2025)

    Loose wet avalanche (D2) on Lichtenberg Mtn

    Photo: Josh Hirshberg

Avalanche Discussion

Preliminary Report: On Friday, February 28, three snowmobilers were riding near Harts Pass in the East North zone when they triggered a large slab avalanche. Two riders were caught and carried. One rider was fully buried and killed. The other was partially buried and injured. NWAC is working with local avalanche professionals to conduct an investigation. Our deepest condolences to the family, friends, and community. (NE, 6,800ft HS-AM-D2.5-R4-O)

The recent snow may have surface crusts, but hasn't fully transitioned into a consolidated snowpack of melt forms. You will likely find a combination of dry snow on northerly aspects and variable, breakable crusts on other aspects. As the surface crusts break down throughout the morning, wet avalanches will become more likely. Plan your day so you can move off of and out from under steep sunny terrain by early afternoon. 

From Feb. 21-25th, the Stevens Pass zone received over 5 inches of water, 1.5 inches of which was snow above 4000ft on Tuesday. There is now about 2 feet of snow over the 2/24 melt-freeze crust. 

On Wednesday, an NWAC forecaster near Stevens Pass got the first post-storm look at upper elevation terrain and observed very large crowns and cornice failures above 6000ft on Rock Mountain and Nason Ridge. They also reported a widespread wet loose avalanche cycle during the day. The reactive storm interfaces from Tuesday were strengthening, but there may be lingering instabilities in very steep, unsupported slopes and confined alpine features. If you use this warm sunny weather to get into the upper elevations, enter more complex terrain cautiously and make frequent assessments before committing to more consequential routes in wind-affected terrain. 

Older observations highlight the widespread wet avalanche cycle that began on Saturday during the atmospheric river. We suspect the rain/snow line over the weekend hovered between 5000 and 6000ft. Many large and very large wet avalanches were reported along the HWY 2 corridor and outside of the Stevens Pass Ski Area.  We are still cataloging this avalanche cycle, so let us know what you see by submitting an observation!

Regioni coperte