Bulletin d’avalanche

East Slopes North

Northwest Avalanche Center
Voir sur la carte

Danger d’avalanche

Sun
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
Open full map
Périmé — ce bulletin a expiré 5 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

The sun may shine on Saturday, but keep your terrain choice conservative while the snowpack adjusts to significant recent snowfalls. Natural avalanches were observed as recently as Thursday, so they still may be easily triggered by people. Wind slabs can be found in open, wind exposed terrain, and loose avalanches can be expected in steep slopes. 

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    2

    Strong winds created wind slabs in many areas the past few days, and may continue on Saturday. You may even find wind thickened storm snow in open areas below treeline. Shooting cracks or hollow-sounding snow are signs you could trigger an avalanche on similar nearby slopes. Avoid wind-loaded, leeward slopes 35 degrees and steeper. Steer around obvious wind features, thickly loaded areas, and unsupported features such as convex rollers.

  • Loose Dry

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

    You could trigger loose avalanches on steep, wind-sheltered slopes in the deep storm snow.  South facing slopes may run with strong sun in the middle of the day. Use clues like rollerballs and wet, sticky snow surfaces to clue you into these. Use caution on steep and unsupported terrain features and around terrain traps like gulleys and cliffs. Use test slopes, hand pits, and snowpack tests to assess how this new snow is bonding. If in doubt, stick to slopes less than 35 degrees.

    Example small loose dry avalanches

Avalanche Discussion

Observers noted a very stormy day on Friday, with lots of wind blown snow. Avalanches were easy to trigger and even ran naturally to size D2 on Thursday. Observers had a close call when a natural avalanche dusted them with a powder cloud from the Cutthroat slide paths on Highway 20. On February 22nd, a strong storm created a widespread, natural avalanche cycle up to size D3 in the area. Most were above treeline near the base of cliffs, though some may have been in wind-sheltered terrain. One notable slide was 1-2ft deep and propagated 300ft across. It appears that all avalanches ran within the recent snow or at the interface of new and old snow. 

Persistent slab avalanches are unlikely but could still exist in the eastern mountains. Have a look at the East Central zone if traveling to the southern or eastern edge of this zone for more details on the crust/facet persistent weak layer that is problematic there. 

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources. Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

Régions couvertes