Bulletin d’avalanche

West Slopes North

Northwest Avalanche Center
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Danger d’avalanche

Wed
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
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Périmé — ce bulletin a expiré 6 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

A mix of new snow problems, sunshine, and a rise in temperatures means tricky and dangerous avalanche conditions will extend into Tuesday.  Low density snow may cover firmer wind transported snow.  Slopes that seem stable in the morning, may release wet loose avalanches by mid-day.     

Problèmes avalancheux

  • Wind Slabs

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

    Whether it's wind drifted snow or new snow storm instabilites, the fresh snowfall will need another day to stabilize.  Trying to determine which slopes were loaded by the strong winds at the start of Monday's storm may not work with lower density snow covering up the usual visual clues.  Feel for firmer wind-stiffened snow and watch for cracking in the new snow as clear signs of instability and a message to stick to lower angle and lower consquence slopes.

    Consider your overhead exposure as well - you might be in the shade but as the sun climbs and snow starts to shed below rock faces, think about natural avalanches that could be triggered from above.  Know what terrain you are connected to and give yourself an extra margin of safety even if you don't see obvious signs of avalanche activity to start the day.  

    (11/28/2020) Skier triggered slab avalanche in the Mt Baker backcountry on a wind loaded slope.

  • Loose Wet

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

    Tuesday's forecast is for sunshine and warming temperatures following fresh snowfall.  That's a recipe for loose wet avalanches. Most will be small but some could be large enough to bury, injure or worse, especially in higher elevation terrain.  Move off steep sunny slopes by late morning and think about the terrain above and below you. 

    Ex: Be on the look out for loose wet avalanches that may trigger larger slides

Avalanche Discussion

The Mt Baker area received 12-16" of snow from Monday's storm. Strong winds that were seen during the first half of the storm backed off toward the end while impressive hourly snowfall rates continued through Monday afternoon. We have no new backcountry observations after a weekend that saw several shallow human triggered soft slabs and one larger natural avalanche release in the Table Mt area. 

Snow depths range from 40-65 inches throughout the North Cascades, and continuous snow begins near 2500-3000ft. Snow coverage is well above average for this time of year, but early season conditions still exist. Stay alert for open creeks, tree wells, crevasses, or other exposed hazards. Consider the consequences when choosing terrain. Falling or getting caught in even a small avalanche could result in a rough ride.

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