Avalanche forecast

Purcells

Dec 26 – 27, 2024Avalanche Canada
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Avalanche danger

Sat
Sun
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low

Highlights

Seek out sheltered, moderate-angled slopes for the best and safest riding.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2

    Fresh, reactive wind slabs are expected to form throughout the day. Avoid wind-loaded areas where the snow surface feels stiff or slabby.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1–2.5

    Buried surface hoar or facets may pose a risk on north-facing slopes, while a buried sun crust could be reactive in south-facing areas.

    In the Invermere area, weak facets and a crust at the base of the snowpack remain a concern.

Confidence

Moderate

Avalanche Summary

On Tuesday, several skier-triggered wind slabs were reported from alpine and treeline terrain. In the Invermere area, several skier-triggered deep persistent slabs (size 1) were reported from NW-NE aspects at treeline and below. A few natural (size 1-2) wind slabs were also reported from alpine terrain.

Looking forward to Wednesday, fresh reactive wind slabs are expected to form in lee areas throughout the day as southwest wind redistributes new snow.

Snowpack Summary

Up to 15 cm of new snow can be expected by end of day Thursday. Southwest winds will redistribute this new snow, forming deeper deposits on leeward slopes at higher elevations.

A layer buried in early December is found roughly 20 to 90 cm below the surface. This layer varies, consisting of weak surface hoar or facetted crystals on shaded slopes and a sun crust with facets on south-facing slopes.

The base of the snowpack is made up of a thick crust and facets in many areas. The only location where this basal layer has shown signs of instability is in the Invermere area.

Weather Summary

Wednesday Night

Mostly cloudy with up to 3 cm of new snow. 15 to 40 km/h southwest ridgetop wind. Treeline temperature -8 °C.

Thursday

Cloudy with up to 10 cm of new snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -5 °C.

Friday

A mix of sun and cloud with isolated flurries. 15 to 30 km/h southwest ridgetop wind. Treeline temperature -7 °C.

Saturday

Cloudy with up to 10 cm of new snow. 30 to 60 km/h southwest wind. Treeline temperature -3 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be careful as you transition into wind-affected terrain.
  • Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Regions covered