Bulletin d’avalanche

Northwest Coastal

Dec 16 – 17, 2022Avalanche Canada
Voir sur la carte
Archivé · expiré 4 years ago

Danger d’avalanche

Sun
Mon
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
Ouvrir la carte complète

Points saillants

With north winds continuing, be aware of the potential for reverse loading and encountering Wind Slabs in places you might not expect them.

Be especially cautious around tree line elevations where the recent snow is more likely to sit on top of a weak layer of preserved surface hoar.

Problèmes avalancheux

  • Wind Slabs

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

    New windslabs will form with northwesterly outflow winds. Winds slabs could overlie a weak layer of surface hoar, facets and/or a crust. Any avalanche in the upper snowpack has the potential to scrub down to these deeper weak layers, making for larger then expected avalanches. This is especially relevant at treeline elevations where surface hoar is more likely larger and better preserved.

Confidence

Moderate

Avalanche Summary

A few small wind slab avalanches were reported in the last 48hrs from the northern part of the region. These avalanches occurred on southeast aspects.

If you head out in the backcountry please support your community by submitting a MIN report!

Snowpack Summary

20 to 50cm of recent snow overlies a layer of surface hoar (buried in early December), sized 5-10 mm. With northwest winds continuing, Wind Slabs have the potential to form on south through southeast aspects and cross-loaded features.

A layer that was buried in mid-November can be found 80 to 120cm deep at treeline and above. This layer consists of a crust below 1200m and a layer of surface hoar above this elevation. This layer has not shown any recent signs of instability.

In the alpine snowpack depths over 2 meters have been reported but the snowpack below treeline is still generally quite shallow.

Weather Summary

Thursday night

Some clouds. No new snow. Wind from the northwest up to 40km/h in the alpine. Temperatures in the alpine around -4˚C.

Friday

Partly cloudy. A chance of light flurries. Wind from the west early in the day shifting to north late in the at 15km/h. A high of -2˚C and a low of -7˚C.

Saturday

Mostly cloudy. Up to 5cm of new snow at the warm air collides with the icoming cold air. Wind from the north at 30km/h. Temperatures starting at -7˚C and dropping to -15˚C by the end of the day.

Sunday

Mostly clear. No new snow. Wind from the north at 20km/h. Temperature plunging to -20˚C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be carefull around freshly wind loaded features.
  • Watch for areas of hard wind slab on alpine features.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.

Régions couvertes