Bulletin d’avalanche

South Rockies

Jan 30, 2019Avalanche Canada
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Archivé · expiré 8 years ago

Danger d’avalanche

Thu
Fri
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
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Points saillants

A weak layer of surface hoar exists primarily at lower elevations. Be suspicious of steep features such as open glades and gullies.

Problèmes avalancheux

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–1.5
    10-30 cm of snow sits on a weak layer of surface hoar (feathery crystals). This layer is most prominent between 1600-1900 m.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    2–3
    The bottom of the snowpack consists of weak facets and depth hoar (sugary snow). Triggering this layer is becoming less likely, but the consequences remain high as avalanches on this layer will be very large and destructive.

Confidence

Moderate - The weather pattern is stable

Weather Forecast

TUESDAY  NIGHT - Clear periods / southwest winds, 15-30 km/h / alpine low temperature near -7WEDNESDAY - A mix of sun and cloud / west winds 20-40 km/h / alpine high temperature near -6THURSDAY - A mix of sun and cloud with isolated flurries / southwest winds 20-30 km/h / alpine high temperature near -5 / freezing level 1500 mFRIDAY - Cloudy with scattered flurries, up to 5 cm / southwest winds, 20-30 km/h / alpine high temperature near -3

Avalanche Summary

No new avalanches were reported on Saturday or Sunday.

Snowpack Summary

10-30 cm of recent snow overlies a weak layer of sun crusts on south facing slopes, and surface hoar (feathery crystals) in sheltered areas. The surface hoar is most prominent at treeline and below. Previous strong winds had formed wind slabs over this weak layer. These may to be susceptible to human triggers.Large variability in snow depths still exists in the region, ranging from almost no snow to nearly 200 cm in some areas. For average snowpack areas, expect to find weak and sugary faceted snow around 50 to 100 cm deep, which extend to the ground. This weak bottom half of the snowpack was the culprit in several large avalanches in the region in the past few weeks.

Régions couvertes