Bulletin d’avalanche

East Purcell

Dec 24 – 25, 2025Avalanche Canada
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Archivé · expiré 9 months ago

Danger d’avalanche

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

Keep an eye out for new wind loading.

New wind slabs are the primary concern on exposed features.

Sheltered terrain holds great riding conditions.

Problèmes avalancheux

  • Wind Slabs

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

    New snow and wind are expected to form wind slabs on northerly aspects during the day on Wednesday.

  • Persistent Slabs

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

    Triggering an avalanche on the mid November layer described in the snowpack summary is unlikely below 2100 m but remains possible above.

    Triggering this layer may require a larger load like a sled, cornice fall or wind slab stepping down.

Confidence

Moderate

  • Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.
  • The snowpack structure is generally well understood.

Avalanche Summary

Sluffing in steep terrain was observed on Monday, no slab avalanches have been observed in the region since Saturday. If you are travelling in the mountains, please submit any observations to the Mountain Information Network.

On Friday near Invermere, an explosive triggered a size 1.5 persistent slab on a north-facing treeline slope, failing on a crust 80–110 cm deep. Over the weekend several rider triggered wind slabs were reported up to size 1.5 on north facing slopes.

Snowpack Summary

Around 20 cm of new snow accompanied by southerly wind is expected by Wednesday afternoon. This falls over 40 to 80 cm of wind affected, settling snow that is generally bonding well to the mid December crust, which is present up to approximately 2100 m.

A thick mid-November crust is buried 70–110 cm deep in eastern terrain, and up to 180 cm in areas with a deeper snowpack. In most areas, faceted grains overlie the crust. Specific, sheltered terrain features have surface hoar present on or near the crust.

Depth hoar (large, weak crystals) are present at the base of the snowpack.

Weather Summary

Tuesday Night

Mostly cloudy with up to 5 cm of snow. 10 to 20 km/h south ridgetop wind. Treeline temperature -6 °C. Freezing level 900 m.

Wednesday

Mostly cloudy with  5 to 15 cm of snow. 30 km/h south ridgetop wind. Treeline temperature -2 °C. Freezing level 1400 m.

Thursday

Mix of sun and clouds with 2 to 5 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

Friday

Mostly cloudy with up to 15 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
  • Be careful with wind-loaded pockets, especially near ridge crests and rollovers.
  • Be mindful that deep instabilities are still present in the snowpack.

Régions couvertes