Bulletin d’avalanche

Kootenay Boundary

Feb 9 – 10, 2012Avalanche Canada
Voir sur la carte
Archivé · expiré 15 years ago

Danger d’avalanche

Sat
Sun
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
Ouvrir la carte complète

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1–3
    Weak wind slabs could be lurking below ridge crests and behind terrain breaks. Watch for reverse-loading from easterly winds, and highly variable cross-loaded slopes.

  • Loose Dry

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2
    Sluffs are running fast and far on steep slopes. Although generally small, they could take you for a ride and terrain traps in the runout can greatly increase the consequences.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    3–7
    Very large avalanches remain a concern in shallow rocky areas with heavy triggers, such as cornice falls and step-down avalanches.

Weather Forecast

A series of weak frontal systems are expected to bring light amounts of fresh snow to the region on Friday, and trace amounts for Saturday and Sunday, but the timing is uncertain. Winds are expected to be generally light southwesterlies, but winds associated with snow squalls could get quite gusty. Freezing levels should remain in valley bottoms but could rise above 1000m with the passage of warm fronts.

Confidence

Good - -1

Avalanche Summary

Fresh hard wind slabs on west through northeast aspects are very touchy with recent natural and skier-triggered avalanches up to Size 2. Loose faceted surface snow is sluffing readily in steep terrain and gaining considerable mass. Deep persistent slab avalanches remain possible with heavy triggers in shallow rocky snowpack areas on unsupported slopes. Check out the Avalanche Image Gallery under the Library tab for some photos of recent deep persistent slab avalanches in the region.

Snowpack Summary

Light amounts of fresh snow has buried the previous snow surface which includes surface hoar up to 30mm at ridgetop and 50mm in valley bottoms, 30cm of near-surface facets on shady sheltered slopes, and surface crusts on sun-exposed slopes. Exposed alpine and treeline areas are wind-affected and variable with scoured areas and pockets of hard wind slab. Concerns remain for the mid-December persistent weakness down around 80-100cm. Basal facets were recently responsible for a large whumpf on a shallow south facing treeline slope in the Rossland Range and gave very easy and sudden compression tests results where they were found down 60cm.

Régions couvertes