Avalanche Forecast

Issued: Dec 19th, 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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Expect wind slab development and reactivity to continue as cold temperatures persist through the week.

Small avalanches on the surface have the potential to scrub down to deeper instabilities, creating larger than expected avalanches.

Summary

Confidence

High

Avalanche Summary

No new avalanches have been reported in 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.

Deeper in the snowpack a widespread crust buried in late November is roughly buried 40-100 cm below the surface. Weak facetted crystals are found immediately above and below this crust.

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

Weather Summary

Monday night

Cloudy with snow, up to 5 cm. Temperatures around -20 C and moderate Southwesterly winds in the alpine.

Tuesday

Cloudy with snow, up to 10 cm. Temperature -15 to -25 C and moderate Westerly winds in the alpine.

Wednesday

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

Thursday

Sunny with periods of cloud, and no precipitation. Temperatures -15 to -25 C and light Northeast 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 20th, 2022 4:00PM