Bulletin d’avalanche

Jasper

Feb 22 – 23, 2018Parks Canada
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Archivé · expiré 9 years ago

Danger d’avalanche

Fri
Sat
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
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Points saillants

Despite the Moderate rating, back-country users should continue to travel conservatively at treeline as a stiff, persistent slab sitting over weak layers will continue to plague the back-country, for the foreseeable future.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1–2.5
    While the winds have abated, they blew hard, and from a variety of directions last week. Windslabs are hard in the alpine and they exist well into treeline areas. These can be expected to be be sensitive to skier triggering.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1.5–3.5
    A stiff slab 50 to 90cm thick, sits over sun crusts on south and west aspects, Surface Hoar preserved at, and just above treeline and weak faceted crystals lurking in shallow snowpack features. This is a dangerous problem that is difficult to avoid.

Weather Forecast

Cold air from the North is insistent on staying in the Park, for now! As the weekend approaches we can expect gradual warming, light snow flurries, and gusting winds from the SW at higher elevations.

Snowpack Summary

15cm snow over the last week, and available snow from the previous storms, has been redistributed by strong winds from variable directions to build slabs and wind effect in open areas. A persistent slab sitting on three weak layers down 50 to 80cm can be found throughout the forecast region and has produced many large avalanches traveling full path

Avalanche Summary

Older windslab to sz 2 observed from a typically cross-loaded alpine features in the Icefields region, SE aspect, 2500m.  An extensive cycle was seen recently, as the persistent slab became overloaded with successive storms. Avalanches to sz 3.5 were observed from most aspects and most elevations with the majority of the action seen around 21-2500m

Confidence

Régions couvertes