Bulletin d’avalanche

Lizard-Flathead

Jan 10, 2018Avalanche Canada
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Archivé · expiré 9 years ago

Danger d’avalanche

Thu
Fri
Alpin
4 · Fort
Limite forestière
4 · Fort
Sous la limite
3 · Marqué
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Points saillants

Very dangerous avalanche conditions. Travel in avalanche terrain is not recommended.

Problèmes avalancheux

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely - Very Likely
    Taille
    2–4
    Touchy weak layers are making for volatile avalanche conditions. Large avalanches are failing naturally and with very easy (even remote) triggers.

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–3
    Recent snow and warming have created widespread storm slabs. If triggered, these could step down to a persistent weak layer and create a surprisingly large avalanche.

Weather Forecast

WEDNESDAY: Light winds. Around 10 cm snow. Alpine temperature near -5.THURSDAY: Light winds. Around 10 cm snow. Alpine temperature near -7.FRIDAY: Strong south-westerly winds. Possible flurries. Alpine temperature near -5

Confidence

Moderate - Forecast snowfall amounts are uncertain on Wednesday

Avalanche Summary

A natural avalanche cycle was observed from the air on Tuesday. It was described as widespread in the Lizard Range, with numerous size 3-3.5 avalanches starting in the alpine and running to near valley floor, and size 2 avalanches at and below treeline. Operators also reported numerous large human, vehicle and remote-triggered avalanches. Expect continuing avalanche activity on Wednesday. The natural cycle will probably slow a little as temperatures cool, but as long as its snowing and blowing, avalanche activity will be likely to continue.On Monday, a skier-triggered size 2 avalanche was reported near McDermott Cabin at around 1800 m.

Snowpack Summary

The snowpack reached its tipping point on Tuesday as warming and precipitation combined to overload persistent weak layers in the snowpack and create a large natural avalanche cycle.A volatile weak layer from mid-December (predominantly feathery surface hoar crystals and/or a sun crust) is found at treeline and below. Deeper in the snowpack, an early season rain crust and sugary facets are also being stressed. Avalanches failing on these layers are large and destructive.

Régions couvertes