Bulletin d’avalanche

West Slopes North

Northwest Avalanche Center
Voir sur la carte

Danger d’avalanche

Tue
Alpin
4 · Fort
Limite forestière
4 · Fort
Sous la limite
4 · Fort
Open full map
Périmé — ce bulletin a expiré 6 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Heavy snow, wind, and rain will likely cause a widespread natural avalanche cycle over the next 24 hours. Avoid exposure to all avalanche terrain.

Problèmes avalancheux

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    2–3

    Expect another 1-2ft of new snow above 4000ft by Monday afternoon, adding to the 1ft+ of new snow from Sunday. The most dangerous conditions will exist in wind-loaded alpine terrain. Avalanches could grow large enough to bury cars or break mature trees and could run full track to valley bottom. Strong and gusty southwest winds will blow, and temperatures will continue to warm over the next 24 hours. Monday will be a good day to wait out the storm and let mother nature run its course. If you do venture out, be certain of your ability to identify and avoid avalanche terrain. 

    (2/14/2021) An example of a large natural avalanche (D2) in motion on Mt. Herman (N, 5000ft). Similar avalanches are very likely Monday. Photo: Pete Durr

  • Loose Wet

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

    Heavy rain Sunday night and Monday will rapidly destabilize the snowpack. This warm and wet event will follow a prolonged period of relatively cold temperatures and low elevation snow.  Wet avalanches are expected in many areas and could grow large. Glide avalanches are even possible in areas below 4000ft. Avoid travel on or below steep slopes and steer clear of avalanche path run out zones.

    (1/14/2021) Example photo of a wet snow avalanche in the West Central zone from a similar weather event earlier this season.

Avalanche Discussion

A strong atmospheric river event will continue to bring a surge of moisture to the North Cascades with the highest precipitation rates set for Sunday night. Avalanche hazard will likely peak overnight, but a natural avalanche cycle may continue through the day Monday. Expect a mix of wet and dry snow avalanche problems and very dangerous conditions at all elevations. 

Several natural and triggered avalanches to destructive size 2 were reported Sunday. Avalanches broke within new and wind drifted snow up to 2ft deep.  On Saturday, a snowboarder triggered and was caught, carried, and partially buried in an avalanche near Huntoon Point. They sustained non-critical injuries and were able to self-rescue with their partners. The avalanche was estimated to be 60ft wide and 1ft+ deep breaking within the recent storm snow.

In addition to very dangerous avalanche conditions, tree well and deep snow immersion hazards are a serious problem with all the recent snow. Find out more information about deep snow safety HERE. 

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