Bulletin d’avalanche

Sea To Sky

Jan 24 – 25, 2012Avalanche Canada
Voir sur la carte
Archivé · expiré 15 years ago

Danger d’avalanche

Thu
Fri
Alpin
4 · Fort
Limite forestière
4 · Fort
Sous la limite
4 · Fort
Ouvrir la carte complète

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    1–6
    Heavy snowfall amounts and strong winds will set up touchy new wind slabs. They may be found in unsuspecting places lower on the slope.

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    1–5
    Heavy amounts of storm snow have fallen on existing cold, low density snow. This has set up an unstable situation in the upper snowpack. With forecast heavy precipitation, strong wind, and rising freezing levels we can expect storm slab avalanches.

Confidence

Fair - Intensity of incoming weather is uncertain on Wednesday

Weather Forecast

Wednesday: Snow amounts up to 15cms. Ridgetop winds 70-90km/hr from the West. Freezing levels should remain at valley bottom. Thursday/Friday: A ridge will build over the coast bringing mainly dry conditions. Few flurries expected up to 5cms. Freezing levels will remain at valley bottom during the day then start to rise in the evening. Ridgetop winds 50-70km/hr from the NW.

Avalanche Summary

Explosive avalanche control have produced slab avalanches up to size 2, @1900m and above on W-N aspects. With forecast snow and wind, we can expect to see a continued avalanche cycle.

Snowpack Summary

An additional 20cms accompanied by strong Southerly winds is forming new wind slabs and storm slabs on the upper snowpack. The upper 50-70cms of the snowpack is resting on a variety of older snow surfaces. These surfaces include previous cold, dry low density snow which may have had seen some faceting, old wind slabs, and crusts. Reports indicate it may be particularly reactive between 1700 and 1800m where a rain crust lies buried approximately 30-50 cm below the snow surface. Reports indicate the bond at this interface is quite good, although the slick nature of the crust may still provide a sliding layer in some steeper locations. This may be a layer of concern with forecast wind, snow and rising freezing levels to come. Previous concerns about deeper persistent weak layers appear to have diminished. Snowpack depths at treeline are in the region of 260 cm.

Régions couvertes