Avalanche Forecast

Issued: Dec 20th, 2022 4:00PM

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

Avalanche Canada isnowsell, Avalanche Canada

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While pushing into bigger terrain assess for wind drifts and firm wind slabs. Small avalanches have the potential to step down to deeper instabilities in large, steep terrain features.

Summary

Confidence

High

Avalanche Summary

A size 1 wind slab, that was ski cut in a wind exposed terrain feature was reported on Monday. Otherwise no new reports over the last few days.

If you head out into the mountains, please share your photos or observations on the Mountain Information Network. Your information helps us understand local conditions!

Snowpack Summary

Up to 10cm of recent, low-density snow continues to facet with cold temperatures. Surface snow is cold, light, and ideal to be redistributed by wind into drifts and stiff wind slabs. The new snow overlays an upper snowpack generally made up of old, settled wind-affected snow and a crust on solar aspects.

A number of buried weak layers deeper in the snowpack remain a concern, despite the lack of recent avalanche activity.

Total snow depths remain low for December with roughly 90 to 140 cm at treeline and up to 200 cm in the alpine.

Weather Summary

Tuesday night

Clearing, with isolated flurries. Temperatures around -25 C and light Northeast winds in the alpine.

Wednesday

Sunny, and no precipitation. Temperatures -15 to -25 C and light Northeast winds.

Thursday

Sunny with periods of cloud, and no precipitation. Temperatures -15 to -25 C and light Northeast winds.

Friday

Cloudy with snow, up to 20 cm. Temperatures of -5 to -10 C, and moderate Southwest winds.

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.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Winds are redistributing the recent low-density snow into potentially reactive windslabs. With cold temperatures, windslabs will likely take longer then usual to stabilize and bond to the underlaying surfaces.

Remember that small wind slabs on the surface could scrub down to deeper weak layers in the snowpack, resulting in bigger then expected avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Weak layers consisting of surface hoar, facets and crusts, buried early in the season remain a concern despite the lack of current avalanche activity. They are buried down roughly 40 to 100 cm from the surface. Watch as the overlaying snow gains cohesion and could make these layers more reactive.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Dec 21st, 2022 4:00PM