Bulletin d’avalanche

Cariboos

Apr 12 – 13, 2012Avalanche Canada
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Archivé · expiré 14 years ago

Danger d’avalanche

Sat
Sun
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
3 · Marqué

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–4
    Forecast wind and new snow will create fresh windslabs on lee terrain at higher elevations.
  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–5
    Large cornices exist in alpine terrain. A failure could be destructive by itself, and could also trigger an avalanche on the slope below.
  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely - Very Likely
    Taille
    1–4
    Forecast rain at lower elevations has the potential to promote ongoing loose wet avalanche activity. Rain can also trigger destructive glide cracks where they exist.

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

Friday: moderate precipitation starting Thursday evening and continuing throughout Friday morning / moderate southeasterly winds / freezing level at 1600m Saturday: cloudy skies with light snowfall / light and variable winds / freezing level at 1600m Sunday: overcast skies with a possibility of clearing in the afternoon / light to moderate easterly winds / freezing level at 1700m

Avalanche Summary

No new avalanches were reported from the region on Wednesday: however, observations were extremely limited. I suspect that there was continued natural wet avalanche activity in response to very warm temperatures and intermittent direct solar radiation. With the current weather pattern, I expect a shift from wet snow avalanches to storm snow instabilities at higher elevations, while wet snow instabilities will still exist below treeline.

Snowpack Summary

Very warm temperatures have dominated the region in recent days and all but the highest, north-facing slopes saw moist to wet surface conditions. As of Thursday morning, slightly cooler temperatures have allowed light amounts of new snow to fall above about 2000m while rain continued to penetrate and weaken the snowpack at lower elevations. Up to 60cm below the surface, you might find a weak crust interface in the alpine and at treeline; however, I suspect that forecast cooling may assist in strengthening this weak layer in most areas. The mid-February buried surface hoar layer is down about 200 cm, although avalanches releasing on this layer represent a very low probability-high consequence scenario. Cornices in the region are very large. With spring temperatures, these are more likely to become weak and fail. They could provide a large enough trigger to release deep layers on slopes below.

Régions couvertes