Bulletin d’avalanche

Purcells

Mar 26 – 27, 2021Avalanche Canada
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Archivé · expiré 6 years ago

Danger d’avalanche

Sun
Mon
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible
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Points saillants

Watch for wind slabs and cornices in steep alpine terrain, and be careful on sunny slopes when the surface is moist or wet.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1–1.5

    Steady wind from the southwest and northwest has left some unstable slabs on steep alpine slopes.

  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely
    Taille
    2–2.5

    Where cornices exist they pose a threat both from the potential to collapse under your feet (or machine) and from the potential to send large chunks of snow far down a slope.

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

FRIDAY NIGHT: Partly cloudy, 40 km/h northwest wind, treeline temperatures around -4 C.

SATURDAY: Mix of sun and cloud, 30-50 km/h southwest wind, freezing level climbing to at least 1800 m, treeline temperatures around -2 C.

SUNDAY: Scattered flurries with 5-15 cm of snow, 40-50 km/h southwest wind, freezing level climbing to 1800 m, treeline temperatures around -2 C.

MONDAY: Another 5-10 cm of snow by the morning then cloudy with isolated flurries during the day, 20 km/h northwest wind, treeline temperatures drop to -8 C.

Avalanche Summary

Recent avalanche activity has been limited to small (size 1-1.5) wind slab avalanches, dry loose sluffs, and cornice falls. These have occurred on a range of aspects, and will continue to be possible on wind-loaded or sun-exposed slopes.

Snowpack Summary

The surface consists of 10-20 cm of dry snow on shady sheltered slopes and moist and crusty surfaces on sun exposed slopes. Gusty westerly winds have formed some isolated wind slabs in lee features. A widespread crust layer from the mid-March warm spell can be found 20-40 cm deep, and small surface hoar has been observed at this depth on some isolated north-facing slopes. Reports suggest the snow is generally well bonded to these layers. Deeper layers are strong and have been unreactive over the past few weeks.

Terrain and Travel

  • Be alert to conditions that change with elevation, aspect and exposure to wind.
  • Carefully evaluate steep lines for wind slabs.
  • Minimize your exposure time below cornices.
  • Minimize exposure to sun-exposed slopes when the solar radiation is strong.

Régions couvertes