Bulletin d’avalanche

Jasper

Dec 28 – 29, 2021
Voir sur la carte
Archivé · expiré 5 years ago

Danger d’avalanche

Wed
Thu
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible

Points saillants

Recent natural activity resulting from cornice failures initiating hard wind slab below ridges.

Cold temps will continue to weaken these unpredictable features and raise the likelihood of initiating large avalanches from lingering deep instabilities.

Problèmes avalancheux

  • Wind Slabs

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

    Up to 35cm of new snow with moderate to strong winds creating wind slabs on lee and cross loaded features. A rain crust 30cm down is a suspect weak layer in BTL.

  • Loose Dry

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

    Extra vigilance is warranted in steep terrain, ice climbs, and gully terrain traps where small avalanches can build into significant volumes.

  • Deep Persistent Slabs

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

    This problem, although stubborn, persists in isolated alpine terrain and may initiate with a large trigger or rapid loading. Use extra caution in thin areas were humans are most likely to trigger this high consequence layer.

Weather Forecast

Tuesday: Cloudy with sunny periods and isolated flurries.

Alpine temp: -20 °C.

Wind N: 10 km/h.

Wednesday: A mix of sun and cloud with isolated flurries.

Alpine temp: Low -29 °C, High -21 °C.

Wind W: 10 km/h.

Thursday: A mix of sun and cloud with isolated flurries.

Alpine Temp: Low -28 °C, High -21 °C.

Wind NW: 10 km/h.

Snowpack Summary

Recent HS redistributed with mod to strong SW winds. Wind slab developed continues on exposed terrain features at treeline and above. The mid-pack is supportive with an exception of a weakening crust interface down 30-40 cm (up to 1950m). Cold temperatures promoting top down facetting through-out the region.

Avalanche Summary

Recent road patrol confirms, it's miserably cold out there!

Two of the most concerning recent observations is the mass of loose dry snow clinging to steep terrain, especially concerning for ice climbers. Watch carefully for any significant overhead features (benches or catchments) still holding recent storm snow and, capped or corniced ridges.

Confidence

Régions couvertes