Bulletin d’avalanche

Banff Yoho Kootenay

Dec 5 – 6, 2013Parks Canada
Voir sur la carte
Archivé · expiré 13 years ago

Danger d’avalanche

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

Points saillants

10-20 cm was received in the forecast area earlier in the week, with the greatest amounts in the Eastern part of the region. Cold temperatures will remain and expect a gradual weakening of the snowpack support.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2
    Reverse loading has created new slabs on southerly aspects. Although less reactive with the colder temperatures, watch out for lingering wind slabs on N-NE aspects.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1–3
    The October melt freeze crust and basal depth hoar are a a concern and avalanches may step down to basal layers. This is primarily a concern on steeper features especially if they are windloaded.

Weather Forecast

The alpine temperatures will dip to -30 by Friday, but become slightly warmer by the weekend to -20C for a high. Winds will remain light from the North. The Arctic high pressure will be in the region for the next several days.

Snowpack Summary

10-15 cm fell with moderate- strong North winds as the Arctic air moved in 2 days ago. Some reverse loading of slopes may have created some new windslabs in the alpine. There is 65-85 cm at our treeline study plots and some mid-pack support for skiing. Field tests still show failures on the Oct 27 crust where it exists or on the basal facets.

Avalanche Summary

In the last 24 hours, a size 2 avalanche occurred on a NW aspect of Copper Mountain, just west of Banff, at about 2350 m. It started as a point release which then triggered a 80 m wide slab that failed near ground, down 100-150 cm.

Confidence

Régions couvertes