Avalanche Forecast

Issued: Feb 1st, 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 and Persistent Slabs.

Avalanche Canada kdevine, Avalanche Canada

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Another round of snow and wind on Monday night and into Tuesday will keep danger elevated. Choose simple objectives with no overhead hazard.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain.

Weather Forecast

MONDAY NIGHT - Snow, 10-20 cm / moderate to strong southwest wind / alpine low temperature near -8 

TUESDAY - Flurries, 5-10 cm / moderate southwest wind / alpine high temperature near -10

WEDNESDAY - Mainly sunny / light northwest wind / alpine high temperature near -10 

THURSDAY - Mainly cloudy with a few flurries / moderate southwest wind / alpine high temperature near -8

Avalanche Summary

A natural avalanche cycle is expected on Monday night during the height of the storm. Widespread avalanches will remain likely on Tuesday.

There were numerous size 1-2 human and explosives triggered storm slab avalanches reported on Sunday.

There were several size 1-2 natural, human, and explosives triggered avalanches reported in the region on Saturday.

Snowpack Summary

With 10-20 cm of new snow expected Monday night, recent storm snow totals are reaching 45-90 cm by Tuesday morning. With an additional 5-10 cm possible on Tuesday, those totals could be reaching 50-100 cm by the end of the day.

This 50-100 cm of fresh snow sits on a recently buried persistent weak layer that consists of facets at upper elevations, surface hoar in sheltered areas, a melt-freeze crust below 1900 m, and a sun crust on south-facing slopes.

A crust from early December may be found around 200+ cm deep in the snowpack. In shallow rocky areas, it may still be possible to trigger this layer. In deeper snowpack areas, it appears to be unreactive.

Terrain and Travel

  • Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.

Problems

Storm Slabs

An icon showing Storm Slabs

Several days of intense snowfall has brought up to 100 cm of new snow to the region, resulting in reactive storm slabs. Human triggered avalanches will be likely throughout the day. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

50-100 cm of snow sits on a widespread weak layer that consists of facets, surface hoar, or a crust depending on location. Avalanches may propagate widely on this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Valid until: Feb 2nd, 2021 4:00PM