Avalanche Forecast

Issued: Dec 21st, 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.

Avalanche Canada trettie, Avalanche Canada

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Watch for wind slab as you gain elevation. Keep it conservative, even a small accident can have big consequences during periods of cold temps and short days.

Check out this blog from our Yukon field team about managing the cold while traveling in avalanche terrain.

Summary

Confidence

High

Avalanche Summary

No new avalanches have been observed in the past few days.

If you are heading into the backcountry please consider filling out a Mountain Information Network report.

Snowpack Summary

Northerly winds have redistributed recent snow into wind slabs on south and east aspects and have cross loaded others. On south facing slopes wind slab could have formed over a sun crust. A layer of surface hoar down around 30cm can be found in sheltered terrain on all aspects up to 2000m, This layer could be a concern where wind slabs form above.

A weak layer consisting of facets and a crust formed in November is now buried around 60cm deep. This layer has produced large avalanches in the past week and continues to show reactivity in snowpack tests in the neighboring forecast region.

In general, the snowpack is quite faceted with average snowpack depths of around 150cm at treeline.

Weather Summary

Wednesday Night

No new snow expected. Light to moderate northeast winds and a Low of -32 at 1800m.

Thursday

Mostly sunny with no new snow expected. Light variable winds and a high of -25 at 1800m.

Friday

Cloudy with trace amounts of new snow expected. Southwest winds increasing to extreme at ridge top. High of -13 at 1800m.

Saturday

Mostly cloudy with trace amounts of new snow expected. Moderate to strong southwest winds and a high of -6 at 1800m.

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.
  • Wind slabs may be poorly bonded to the underlying crust.

Problems

Wind Slabs

An icon showing Wind Slabs

Northeast winds will likely have formed wind slab on south and west aspects at treeline and above. On south facing terrain these wind slabs could sit over a thin sun crust. In sheltered terrain at treeline wind slabs could sit on a layer of surface hoar. Triggering a wind slab over surface hoar or a crust could result in a larger avalanche.

Aspects: East, South East, South, South West, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Dec 22nd, 2022 4:00PM