Bulletin d’avalanche

Kootenay Boundary

Feb 10 – 11, 2013Avalanche Canada
Voir sur la carte
Archivé · expiré 14 years ago

Danger d’avalanche

Tue
Wed
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
Ouvrir la carte complète

Points saillants

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–3
    Triggering is possible on steep gully sidewalls and in the lee of ridge crests.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1–4
    An assortment of weak crystals is buried between 35 and 50cm below the surface. Although this interface is gaining strength, triggering may still be possible in unsupported terrain.

Confidence

Fair - Intensity of incoming weather is uncertain on Tuesday

Weather Forecast

Synopsis: The ridge of high pressure that has brought clear weather starts to erode and allows a frontal system to move in, bringing precipitation on Tuesday.Monday: Dry until late in the day, with increasing cloud cover through the day. Freezing level around 600m in the afternoon. Light westerly winds.Tuesday: Around 5cm new snow. Freezing level around 1400m in the afternnon. Westerly winds gusting to 70 km/h at ridgetop.Wednesday: Flurries or light snow in the morning, dry in the afternoon. Freezing level 1000m in the morning, dropping to valley bottom by the afternoon. Moderate NW winds.

Avalanche Summary

There were two size 1 human-triggered avalanches reported from Saturday on north aspects in recent new snow with crowns of 10-20 cm. Loose snow avalanches were reported over the weekend on steep solar aspects.

Snowpack Summary

The snow surface consists of a sun crust, surface hoar, or a dusting of new snow. Below this approximately 15-20 cm of recent storm snow has been redistributed into soft wind slabs at higher elevations. The new snow overlies a gamut of old surfaces which include old wind slabs at higher elevations, fairly widespread surface hoar, and a melt-freeze crust on previously sun-exposed slopes. This interface will be something to watch as the overlying slab develops. About 35-50cm below the surface is another interface of surface hoar or a sun crust that was buried on Jan 23. It is hard to find in some areas and seems to be gaining strength where it is found, but this weakness is still on the radar of professionals in the region. The snowpack below this is generally well settled and bonded.

Régions couvertes