Bulletin d’avalanche

Purcells

Dec 29 – 30, 2015Avalanche Canada
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Archivé · expiré 11 years ago

Danger d’avalanche

Thu
Fri
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible

Points saillants

Conditions are variable across the Purcells. In isolated areas, a persistent weak layer may still be reactive to human triggers. Take the time to investigate your local snowpack.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2
    Soft wind slabs may be reactive to the weight of a person below ridges and ribs.
  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely
    Taille
    2–4
    A weak layer buried about 40-100 cm down remains reactive in snowpack tests in some areas. It has produced avalanches within the last week.

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

A cool, dry spell is starting. Expect light northerly winds, sun and slightly milder temperatures in the alpine; and cloud and cold temperatures in the valleys.For more details check out https://avalanche.ca/weather.

Avalanche Summary

Over the last few days, several small loose dry avalanches and one size 1.5 wind slab have been observed. Persistent slabs were last triggered about a week ago. Unfortunately these types of problems don't heal quickly, so they remain on our radar.

Snowpack Summary

20-30 cm of low-density snow typically overlies a well-settled mid and lower snowpack. Surface hoar and near-surface facets may be mingled within the upper few cm. Storm slab properties may change and become more cohesive as the alpine gets some sun and warmer temperatures. Wind slabs, found in the lee of ridges and ribs, are still reactive in some spots and healing in others.A weak layer which was buried in early December is down about 40-100 cm. At and below treeline, it mainly consists of large surface hoar. At higher elevations, it consists of a sun crust, facets, and/or small surface hoar. This layer is still reactive in some snowpack tests and has produced at least one human-triggered avalanche in the last week. The persistent slab is a low probability, high consequence problem. Below this layer, the snowpack is thought to be generally strong and well-settled.

Régions couvertes