Bulletin d’avalanche

East Slopes North

Northwest Avalanche Center
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Danger d’avalanche

Sat
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible
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Périmé — ce bulletin a expiré 3 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

You may still be able to trigger slab avalanches in wind-drifted snow at upper elevations. Look for cracks shoot through the snow, and recently formed cornices or pillows of snow.  If you see these indicators, steer around steep wind-loaded features and stick to wind-sheltered terrain or lower-angle slopes.

Problèmes avalancheux

  • Wind Slabs

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

    While you may still be able trigger these avalanches, they're becoming less likely. Southwest winds transported snow Monday through Wednesday. Look for clues like cracks shooting through the snow, sharp cornices, and areas of stiffer and deeper snow near to areas that are shallower. You can avoid triggering these avalanches by steering around common trigger points like bulging pillows of snow and convex rollovers. You can also stick to wind sheltered terrain or slopes less than 35 degrees.

    (12/13/2023)

    A natural avalanche (likely the night of Dec 12th) at the top of Liberty Bowl on Blue Lake Peak, Washington Pass. SS-N-D1. NW, 7,700ft

    Photo: Matt Primomo

Avalanche Discussion

The mountains picked up 1-3" of snow on Thursday even as far east as the Silverstar trailhead. Observers reported widespread surface hoar on a variety of slopes prior to the light accumulations. On Tuesday and Wednesday, observers reported blowing snow, signs of wind transport, and even the avalanche pictured above. This wasn't a major wind even, but just enought to raise the avalanche danger.

Near the Cascade crest, you'll find a breakable crust near the surface in terrain below 6300-6500 ft, that was formed from rain on December 10th. Well east of the Cascade crest, thecrust is thinner and it's disapears in some places under tree canopy. An older crust (12/7) is about  16" below the snow surface. 

Last Sunday brought rain and wet avalanches following about 10-14" of recent snow. You can see some of these avalanches near  Washington Pass here and at Harts Pass here.

Looking further ahead, we anticipate a major warm up along with some clearing on Saturday. This may be enough for heightened avalanche danger due to wet avalanches. Keep an eye on the latest avalanche and weather forecasts to see how they change.

Régions couvertes