Bulletin d’avalanche

Purcells

Apr 9 – 10, 2014Avalanche Canada
Voir sur la carte
Archivé · expiré 12 years ago

Danger d’avalanche

Fri
Sat
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré

Points saillants

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–3
    Wind slabs immediately lee of ridge crest and mid slope features may still be sensitive to human triggering. Keep an eye on overhead cornices too, you don't want to be underneath or on top of one when it releases.
  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    4–8
    A bomber spring snowpack is still a few weeks away. For now, the potential for very large deep slab avalanches needs to remain on your radar. Cornice fall, strong solar, warming temps or a surface avalanche in motion could wake the sleeping giant.

Confidence

Fair

Weather Forecast

Synopsis: A weak and dirty ridge lingers over the Purcells resulting in trace amounts of precipitation, partially cloudy skies and a nice melt freeze pattern for the forecast period.Thursday: Freezing Level: 1200m rising to 2100m; Precipitation: Trace; Wind: Treeline: Light, West | Ridgetop: Moderate, WFriday: Freezing Level: 1500m rising to 2000m; Precipitation: Trace; Wind: Treeline: Light, W | Ridgetop: Moderate, W/NWSaturday: Freezing Level: Valley Bottom rising to 1600m; Precipitation: 1:2mm - 1:3cm; Wind: Treeline: Light, NE | Ridgetop: Moderate, W/NW

Avalanche Summary

Avalanche activity on Tuesday was limited to loose wet avalanches to size 1.5, mostly from solar aspects. No other significant activity to report.

Snowpack Summary

Warm temperatures resulted in the freezing level reaching to almost 2400m early this week in the southern Purcells, around 1800m in the north. This has helped to settle out last weeks storm snow, it's reported to be bonding well to the old surface. Strong winds out of both the SW and NW have redistributed what little dry snow still exists at upper treeline and alpine elevations into wind slabs that are most prevalent immediately lee of ridge crest Three persistent weak layers exist in the highly variable snowpack of the Purcells:The mid-March sun crust/surface hoar layer down 50-80cm still has potential for human-triggering in isolated areas. The early-March crust/facet/surface hoar layer down around 80-120cm has become less susceptible to human triggering, but still has the capacity to produce large avalanches.The mid-February crust/facet/surface hoar combo is typically down 60 - 120cm. Direct triggering of this layer has become unlikely, however, cornice fall, a smaller avalanche in motion or prolonged warming may wake this layer up, which would result in very large and destructive avalanches.Weak basal facets exist in many areas, but triggering is unlikely.

Régions couvertes