Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
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Pericolo valanghe

Sun
Alta quota
4 · Forte
Limite del bosco
4 · Forte
Sotto il limite
3 · Marcato
Non aggiornato — questo bollettino è scaduto 3 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Heavy snow and strong wind will create very dangerous conditions. Avoid slopes over 35 degrees, especially at middle to upper elevations. Avalanches will run naturally, they'll be very easy to trigger, and many could be big enough to bury or kill you. 

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Very Likely
    Dimensione
    1.5–2

    Only travel in the backcountry if you're confident in avoiding avalanche terrain. Expect avalanches on most slopes over 35 degrees. Be extra careful to avoid being under slopes where natural avalanches could come down from above. Anticipate more dangerous conditions as you gain elevation.  Natural avalanches and cracks shooting through the snow are warning signs of very dangerous conditions.

    Avalanches will likely involve all of the recent snow that has accumulated since Thursday. Some could even gouge deeper into older snow. Avalanches could be 2-3 feet deep and easier to trigger where you find stiffer snow on leeward slopes and wind-exposed terrain. Use quick tests and small slopes to check how easily the new snow slides before traveling near steeper terrain. 

    (12/1/2023)

    A small storm slab avalanche in 6-8" of new snow. The new/old interface was very reactive. Expect these avalanches to be close to 1.5-2 feet dep on Saturday. Rock Mtn

    Photo: Matt Primomo

Avalanche Discussion

On Friday, observers on Rock Mountain and in the backcountry near Stevens Pass Resort reported numerous small natural avalanches and slopes that slide easily with the weight of a skier. They found widespread surface hoar and a crust (up to at least 6,500ft) at the recently buried interface.

On Thursday, snow buried various weak layers like facets, surface hoar, and slick crusts that formed during over a week of dry weather. As of Friday, cold temperatures wrung out 8-12" of low-density snow.  We anticipate avalanches will run on this interface and could be large at mid to upper elevations. The weak layers at the 11/30 interface may be the source of avalanches for some time. The coming week will bring intense storms and, at times, warm temperatures. We expect even more dangerous avalanche conditions as heavy snow (and rain) accumulates.

It's still early season, and our confidence in the avalanche forecast is low. Approach mountain travel with caution and be ready to make your own assessments. Snow cover is still shallow in many places. Before this week's storm, snow cover was minimal to nonexistent below 4,500ft, especially on sun-exposed slopes. Hitting buried rocks, stumps, and creeks may be your most significant hazard of the day.

Anyone can add to the forecast. Let us know what you see in the mountains by submitting an observation.

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