Bollettino valanghe

West Slopes North

Northwest Avalanche Center
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Pericolo valanghe

Wed
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 8 months ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Use lower-angle terrain to get around steep slopes holding recently wind-drifted snow. Keep an eye out for pillowy or rounded drifts and areas of stiffer snow. Deep, unconsolidated snow and barely covered hazards also increase the risk of collisions and immersion accidents.

Problemi valanghivi

  • Wind Slabs

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

    Strong winds and snowfall late in the evening should taper by morning, but still leave pesky wind slabs in their wake. They should be most reactive first thing in the morning and slowly gain strength through the day. Wind slabs are commonly found on the leeward side of ridgelines, below cornices, and along gully walls. With strong winds and low-elevation snow, don’t rule them out down low either.

    Use visual clues like rippled snow, cornices, and scoured surfaces to identify wind-loaded terrain. Stiffer snow is also a sign wind slabs could lurk nearby. Small test slopes and quick hand pits can help gauge how well new slabs are bonding before committing to bigger terrain.

    (3/5/2025)

    Even very soft snow can show the signs of wind transport. 

    Photo: Robert Hahn

Avalanche Discussion

Avalanche danger tomorrow will waver between Moderate and Considerable. As usual, a lot of it has to do with how much wind and snow each part of the forecast zone receives. Another factor for Tuesday is timing. An elevation band that would qualify as Considerable right out of the gate can easily notch down to Moderate by the afternoon. Get a read on snow stability and use terrain features to your advantage before diving into steeper or more complex terrain.

Observers in the Baker Backcountry found reactive but generally small wind slabs on Monday. While many steep wind-loaded slopes produced slabs or shooting cracks, no slab avalanches and minimal sluffing were reported from wind-sheltered terrain. A handful of large, partly filled-in crowns were observed on the north side of Table Mountain. While the exact time of occurrence is unknown, they appeared to be a day or two old.

The 3–5 feet of snow that has fallen since Thursday night is beginning to settle into a single, mostly uniform layer over the December 18 crust. Aside from test slopes and pits in wind-loaded terrain, snowpack testing only produced resistant results at the old-new snow interface found about 18" from the surface. No avalanche or snowpack observations were submitted from other parts of the forecast zone.

Two snow immersion incidents were reported on Sunday and another on Monday. Fortunately, no injuries were reported. The mountains have gone from thinly covered to sporting a legitimate snowpack in just a few days. This snow is unconsolidated, and tree wells are even more dangerous than usual. Keep your partners in sight and have a plan to get back uphill or call for assistance from above if someone gets trapped in deep snow.

State and local resources are working diligently to reduce the impacts of destructive storms that occurred earlier this month. We can help by respecting affected communities, complying with road closures, and adhering to ski area uphill travel policies.

Regioni coperte