Bulletin d’avalanche

Lizard-Flathead

Dec 25 – 26, 2018Avalanche Canada
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Archivé · expiré 8 years ago

Danger d’avalanche

Thu
Fri
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
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Points saillants

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Problèmes avalancheux

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    2–3
    60-110 cm of snow sits on a weak layer that consists primarily of facets (sugary snow). Winds have redistributed recent snow and slabs may be more reactive in wind-loaded terrain.

Confidence

Moderate -

Weather Forecast

TUESDAY NIGHT: Clear. Light southwest wind. Alpine low of -12C.WEDNESDAY: Cloudy with isolated flurries, trace accumulation. Light southwest wind. Alpine high of -9C.THURSDAY: Mix of sun and cloud. Light northwest wind. Alpine high of -9C.FRIDAY: Mix of sun and cloud. Light increasing to moderate west wind. Alpine high of -11C.

Avalanche Summary

Over the weekend, explosives triggered avalanches to size 2.5 and natural avalanches to size 2 were reported. On Sunday, wind redistributing new snow resulted in numerous natural wind slabs avalanches (size 1) noted in the region.

Snowpack Summary

Up to 20 cm of new snow is being redistributed into soft wind slabs in lee areas at treeline and alpine elevations. A combined total of 60-110 cm of recent snow has formed a slab that sits on a persistent weak layer that formed in early December. This layer mostly consists of facets (sugary snow) with some isolated areas also containing small surface hoar (feathery crystals). Several other weak layers have been observed in the lower snowpack such as crusts and facets that formed in late October/early November. The potential may exist for avalanches triggered on the persistent slab to step down to these lower layers, resulting in large, destructive avalanches.

Régions couvertes