Bulletin d’avalanche

South Coast

Feb 22 – 23, 2025Avalanche Canada
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Archivé · expiré 2 years ago

Danger d’avalanche

Mon
Tue
Alpin
4 · Fort
Limite forestière
4 · Fort
Sous la limite
3 · Marqué

Points saillants

Heavy precipitation combined with warm temperatures create very dangerous avalanche conditions. Natural avalanches are likely, and human triggered avalanches are very likely.

Problèmes avalancheux

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1.5–3

    Increased load on the January drought layer may cause it to become active again. Small storm avalanches may step down to this layer.

  • Storm Slabs

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

    The recent storm snow is not bonding well to the underlying weak layers. This problem is most prevelant at treeline and above in wind loaded features.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    1–1.5

    Warming temperatures combined with precipitation will increase likelihood of wet loose avalanches.

Confidence

Moderate

Avalanche Summary

Recent explosive control produced small storm slab avalanches on the North shore.

Over the weekend, the new storm snow was showing poor bonding to underlying weak layers. As the storm snow continues to pile up, these layers may produce large avalanches.

Snowpack Summary

Up to 70 mm of precipitation has fallen across the coast over the past three days. In sheltered terrain this new snow may overlie soft, faceted snow or surface hoar. In exposed terrain it will overlie a sun crust or wind-affected snow.

A late-January weak layer (hard crust, facets, or surface hoar) is buried 80 to 120 cm deep, this layer could become reactive the more the precipitation adds load on it.

The lower snowpack is strong and bonded.

Weather Summary

Friday Night

Cloudy with 20 to 40 mm of mixed precipitation. 40 to 60 km/h southwest ridgetop wind. Freezing level 1600 m.

Saturday

Cloudy with 40 to 60 mm of precipitation. 40 to 80 km/h southwest ridgetop wind. Freezing level rising to 2000 m.

Sunday

Cloudy with 10 to 15 mm of precipitation. 40 to 70 km/h south ridgetop wind. Freezing level 1800 m.

Monday

Cloudy with 30 to 50 mm of precipitation. 40 to 70 km/h southwest ridgetop wind. Freezing level 1200 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Closely monitor how the new snow is bonding to the old surface.
  • Be aware of the potential for large avalanches due to buried weak layers.
  • A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.

Régions couvertes