Avalanche Forecast

Issued: Dec 13th, 2020 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 ahanna, Avalanche Canada

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Watch for wind loaded pockets of snow especially around ridge crests and roll-overs in the alpine.

Summary

Confidence

Moderate -

Weather Forecast

Sunday night: Trace to 5 cm of new snow, light southwest ridgetop wind freezing level 600 m.

Monday: Trace to 5 cm new snow, light southwest ridgetop wind, alpine high -6 C, freezing level 900 m.

Tuesday: 10-20 cm new snow, strong southwest ridgetop wind, alpine high -5 C, freezing level 1000 m.

Wednesday: 5-15 cm new snow, moderate southwest ridgetop wind, alpine high -4 C, freezing level 1200 m.

Watch Meteorologist David Jones' Whistler Powder Picker weather forecast here.

Avalanche Summary

On Sunday, small but stiff skier controlled size 1 wind slabs were reported running on the crust.

Solar triggered loose snow avalanches size 1-2 were reported on steep solar aspects in the alpine on Saturday. A size 1.5 natural cornice fall was also reported in this MIN from the Garabaldi area.

Have you been out and about in the mountains? If so please submit your observations to the Mountain Information Network (MIN). It doesn't have to be technical - photos are especially helpful! Thank you so much for all the great MINs submitted so far! 

Snowpack Summary

Brief strong southwest wind has formed soft wind slabs over a supportive crust in the alpine. In wind sheltered areas, a layer of surface hoar may be found shallowly buried within the 10-30 cm above the crust. Below 2000 m the crust may be somewhat punchy with a moist snowpack below. 

Snowpack depths change rapidly with elevation, with 0-50 cm below treeline to 150 cm in the alpine.

Terrain and Travel

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Be alert to conditions that change with elevation and wind exposure.
  • Keep in mind the crust offers an excellent bed surface for avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent strong southeast to southwest wind has transported soft snow into pockets of wind slab in leeward terrain features such as ridge crests and roll-overs. The near surface crust offers a slick bed surface for avalanches.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Dec 14th, 2020 4:00PM