Bulletin d’avalanche

East Slopes Central

Northwest Avalanche Center
Voir sur la carte

Danger d’avalanche

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

Points saillants

Round after round of snow and wind continue to build fresh slabs along exposed ridges and near the base of cliffs. Shallow wind drifts may trigger easily, while deeper slabs may or may not fail. Don’t trust steep wind-loaded slopes on Monday.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    At this point, we’re dealing with two different wind slab issues. One should be easy to spot and manage. The other will be a bit more hidden, but much less likely. 

    You’ll probably see blowing snow, fresh drifts, and textured surfaces that help you determine where the wind is building new slabs. Small slope tests may give a quick clue of how they might react to your weight. If they fail easily or the slope is above a cliff or wall of trees, simply avoid the wind-loaded pocket. 

    A few isolated larger wind slabs could still linger from earlier this weekend. These hard slabs may be tough to spot under the fresh snow. Instead, you’ll need to hunt for them using large clues like scoured slopes and cornice lines to anticipate where these beasts could lie. These slabs will be most likely to trigger on very steep terrain, convex features, or unsupported slopes.

    (12/13/2024)

    Example: Is it windy? Don't overlook the obvious. Blowing snow should mean wind slabs until proven otherwise. 

    Photo: ONP Rangers

Avalanche Discussion

The parade of storms just keeps coming across the East Central zone. A system Sunday night into Monday morning should result in the most dangerous conditions occurring right out of the gate. As winds start to ease and precipitation wains, your chance of triggering a slide should slowly decrease. 

This latest round of snow comes on the heels of two other systems from the weekend. As of Sunday evening, storm totals from the zone range from 8-14 inches. Reports from Blewett Pass, as well as nearby zones, suggest loose fluffy snow outside of wind-affected areas. Several small loose dry avalanches have even been reported. 

While you might find a subtle weak layer within all this storm snow, it’s really the old snow interface where we have the most questions. An NWAC forecaster on the east side of the Stevens zone found small buried surfaces hoar about 16 inches (40cm) below the surface. Old slick crusts, surface hoar, and facets were all reported prior to this round of storms. So far, we haven’t heard of any avalanches on these layers, but it's worth keeping an eye on. 

This series of storms has significantly helped lower elevation snowpacks. Even still, conditions are thin and that brings its own set of hazards. Don’t be in a hurry while traveling in these thin early-season conditions.

Régions couvertes