Bulletin d’avalanche

Jasper

Apr 24 – 25, 2023Avalanche Canada
Voir sur la carte
Archivé · expiré 3 years ago

Danger d’avalanche

Wed
Thu
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
Sans niveau

Points saillants

The trend for the next few days is less overnight freeze and increasing freezing levels raising the potential of increased reactivity. Your strategy is to start and end early, avoid cornices, and anticipate natural activity to escalate with full depth releases possible.

Problèmes avalancheux

  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    2–3

    Cornices are large and ominous. The rising freezing levels will weaken them. When they fall, they can trigger large avalanches or just be a hazard by their sheer mass.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–2

    This problem will be increasing in frequency the next few days as less overnight freeze occurs and rising daytime freezing levels.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    2–4

    The bottom of the snowpack is inherently weak with well-developed Facets and Depth Hoar. The next few days could see this problem moving into the reactive category with dramatically rising freezing levels.

Confidence

Low

Avalanche Summary

Monday's Maligne and Icefield's patrols noted nothing new. There was an avalanche Fatality in Banff Park near Lake Louise Saturday from a deep large human triggered slide. Last week a few large cornice triggered avalanches were noted on Alpine East aspects.

Post avalanche observations to the MIN.

Snowpack Summary

A dusting of snow overnight rests on sun crusts on solar aspects and a melt-freeze crust below tree line. Old wind slabs are on exposed alpine terrain. A layer of sun crust or facets linger in the mid-pack. The main concern is the depth hoar and basal facets at the bottom causing our deep persistent slab problem.

Weather Summary

Parkers ridge weather on Monday night will be clear and -4 °C. Tuesday is sun, cloud, flurries, -2 °C, and 1900m freezing level. Wednesday's freezing level is forecast to increase to 2500m and Thursday's will be 3000m.

Terrain and Travel Advice

  • Cornices become weak with daytime heating.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Avoid exposure to slopes that have cornices overhead.

Régions couvertes