Avalanche Forecast

Issued: Nov 30th, 2021 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs.

Avalanche Canada swerner, Avalanche Canada

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More snow and cranking wind is keeping the avalanche danger HIGH. Storm slabs will likely be reactive on Wednesday. Be patient as the recent storm snow needs time to settle and stabilize.

Summary

Confidence

Moderate - Recent weather patterns have resulted in a high degree of snowpack variability within the region.

Weather Forecast

Tuesday Night: Snow 5-10 cm. Alpine temperatures near -5 and freezing levels 700 m. Ridgetop wind remains strong from the southwest.

Wednesday: snow 10-20 cm. Alpine temperatures -8 and freezIng levels 600 m. Ridgetop wind strong to extreme from the southwest.

Thursday: Trace of snow. Alpine temperatures near -12 and freezing levels valley bottom. Ridgetop wind strong from the southwest.Ridgetop wind strong from the southwest. 

Avalanche Summary

Natural avalanche activity will persist through Wednesday with additional snow and cranking winds. 

Few natural avalanches (size 2) were reported over the weekend in the alpine. 

Snowpack Summary

Varied amounts of new snow fell over the region. 10-20 cm over the southern half and up to 40 cm over the northern half. New snow and strong winds have likely formed new and reactive storm slabs. These slabs will be especially deep on leeward features on north aspects. In specific alpine areas, storm and buried wind slabs are sitting on a hard crust.

A crust formed in early November and has been reported down 80-120 cm. There has been some evidence of large avalanches running on this crust. This will be a layer to monitor throughout the season.

Treeline snow depths are estimated to be 100-150 cm.

Terrain and Travel

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Avoid traveling in runout zones. Avalanches have the potential to run to the valley floor.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow and strong ridgetop wind have likely formed reactive storm slabs. Deeper slabs will exist on leeward slopes and behind terrain features. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely - Almost Certain

Expected Size

1 - 3

Valid until: Dec 1st, 2021 4:00PM