Avalanche Forecast

Issued: Dec 28th, 2024 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs and Persistent Slabs.

Avalanche Canada Avalanche Canada, Avalanche Canada

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Continue to make conservative terrain choices while the storm snow settles and stabilizes.

Uncertainty lies deeper in the snowpack, where dangerous weak layers may be at play.

Summary

Confidence

Moderate

Avalanche Summary

Skier traffic produced small loose dry avalanches on steep slopes at treeline throughout the region Saturday.

On Friday, a large persistent slab (size 3) was observed at 2000 m in the Bonnington Range. The trigger is unknown, but the propagation was wide.

Recent natural widespread avalanche activity was reported in Stagleap Provincial Park where numerous storm slabs (size 1 to 1.5) were observed from steep terrain.

Snowpack Summary

Continued snowfalls adds to the 25 to 45 cm of recent snow. Moderate southwest wind has redistributed this new snow, forming deeper deposits on leeward slopes at higher elevations.

Below this new snow, a thin crust is present near the surface below approximately 1600 m.

Weak layers of surface hoar or facets and a crust may persist in the mid-snowpack, and snowpack tests continue to indicate potential instability.

The lower snowpack is generally strong and well-bonded.

Weather Summary

Saturday Night

Cloudy with 5 to 10 cm of new snow. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -4 °C.

Sunday

Cloudy with up to 5 cm of new snow. 10 to 20 km/h northeast ridgetop wind. Treeline temperature -5 °C.

Monday

Mostly cloudy with isolated flurries. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -6 °C.

Tuesday

Mostly cloudy with isolated flurries. 10 to 20 km/h souhtwest ridgetop wind. Treeline temperature -8 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • In times of uncertainty, conservative terrain choices are our best defense.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Problems

Storm Slabs

An icon showing Storm Slabs

Recent snowfall and southwest winds have formed fresh storm slabs that will be deepest and most reactive in wind-loaded areas.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Buried weak layers of surface hoar and facets on a crust are now buried 50 to 120 cm deep. Increased load from new snow may make these layers more reactive. Be especially cautious on steep, open slopes at treeline and below.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Dec 29th, 2024 4:00PM

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