Avalanche Forecast

Issued: Dec 24th, 2023 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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A persistent weak layer of surface hoar has been reactive to human-triggering in recent days. The safest way to manage this problem is through conservative terrain choices.

Summary

Confidence

Moderate

Avalanche Summary

A natural avalanche cycle occurred in the past few days. Several rider triggered slab avalanches have also been reported.

Check out this MIN from Powder King, detailing a skier-triggered persistent slab. This MIN shows several avalanches that occurred in Torpy on Friday. We suspect that these avalanches ran on one of the surface hoar layers in the top meter of the snowpack.

Looking forward to Monday, reactivity is expected to persist with wind and warm temperatures.

Snowpack Summary

Recent storm snow has been redistributed into wind slab near ridge crests by southerly winds. Below treeline a new crust is on or near the surface.

The mid pack contains several layers of note; a layer of surface hoar and a crust down 20 to 30 cm , a significant crust from the early December rain event down around 50 cm and a layer of surface hoar down 60 to 100 cm.

Snowpack depth throughout this region is highly variable and as a result the depths of the above mentioned layers are approximate and could be different than what you find in your riding area.

Weather Summary

Sunday Night

Clear periods with no new snow. South alpine wind, 30 to 60 km/h. Treeline temperature -6°C.

Monday

Cloudy with sunny periods, no new snow. South alpine wind, 30 to 70 km/h. Treeline temperature reach a high of -1 °C.

Tuesday

Cloudy with snowfall, 1 to 10 cm of accumulation. South alpine wind, 40 to 100 km/h. Treeline temperature 0 °C.

Wednesday

Mainly cloudy with isolated flurries. South alpine wind, 30 to 60 km/h. Treeline temperature -1 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Uncertainty is best managed through conservative terrain choices at this time.
  • Any steep opening in the trees should be treated as suspect right now.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

Problems

Persistent Slabs

An icon showing Persistent Slabs

Buried surface hoar remains rider triggerable. This layer is a concern in areas where a significant crust is not found above it.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Wind Slabs

An icon showing Wind Slabs

Wind slabs may remain sensitive to rider traffic at treeline and above. Avoid wind-loaded areas and watch for fresh, reactive slabs forming throughout the day.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 25th, 2023 4:00PM