Bulletin d’avalanche

Purcells

Feb 9 – 10, 2016Avalanche Canada
Voir sur la carte
Archivé · expiré 11 years ago

Danger d’avalanche

Thu
Fri
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
Ouvrir la carte complète

Points saillants

Warm temperatures and sun-exposure are maintaining an elevated avalanche danger. Keep it conservative until things cool off and the snowpack settles.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–4
    Recently formed wind slabs may still be able to be triggered by the weight of a person. Cornices are likely to be fragile in the hot weather.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    3–5
    A deeply buried weak layer can still be triggered in some places, creating very large avalanches. Forecast warming may increase the sensitivity of this problem.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely - Very Likely
    Taille
    1–3
    Strong sunshine and warm temperatures are expected to weaken surface snow layers and cause loose wet avalanches or wet slabs.

Confidence

High

Weather Forecast

WEDNESDAY: Mainly sunny with increasing cloud throughout the day and light southwesterly winds. A temperature inversion is expected to maintain well above freezing temperatures at treeline and alpine elevations. THURSDAY: Mainly clear and dry with freezing levels dropping to near 2000m and light variable winds. FRIDAY: Light snow possible with freezing levels dropping to valley bottoms and light southwesterly winds.

Avalanche Summary

Reports from Monday include numerous natural wet loose sluffs up to Size 1.5 in response to warm temperatures and direct sun-exposure, limited primarily to steep slopes in the afternoon.

Snowpack Summary

The surface snow is becoming moist and cohesionless, and cornices are getting weak throughout the day with warm temperatures and direct sun-exposure. Strong to extreme winds on Saturday created wind slabs and cornices in many areas, and scoured north and west-facing alpine slopes. The early January surface hoar/ facet layer is typically down 70-90 cm. Recent very large avalanches have been failing on this interface in the north of the region (see avalanche discussion). In general, the lower snowpack below this layer is well settled and strong, apart from some thin snowpack areas where basal facets exist.

Régions couvertes