Avalanche Forecast

Issued: Jan 8th, 2021 4:00PM

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

Avalanche Canada MBender, Avalanche Canada

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 Heightened avalanche conditions exist on wind loaded slopes. In the north of the region, the likelihood of triggering deeply buried weak weak layers is reducing, however the consequences of doing so are still high. 

Summary

Confidence

Moderate - Uncertainty is due to extremely variable snowpack conditions reported through the region.

Weather Forecast

Friday Night: Mainly cloudy, light southwest wind, alpine high -7, freezing level 500 m.

Saturday: Mainly cloudy with sunny breaks, light to moderate southwest wind, alpine high -5, freezing level 700 m.

Sunday: Mainly cloudy with flurries, moderate southwest wind, alpine high -3, freezing level 900 m.

Monday: Periods of snow, moderate to strong southwest wind, alpine high -1, freezing level 1200 m.

Avalanche Summary

Reports from Wednesday include a human triggered size 2 storm slab avalanche at 2000 m on a north aspect in the Duffey Lake area. As well a few natural size 1-1.5 naturally triggered windslabs in the alpine. On Tuesday there was a size 2 persistent slab avalanche reported on Joffre Shoulder. See this MIN report for more details.

Snowpack Summary

Snow from last week has been redistributed at upper elevations. In sheltered areas below treeline, the most recent snow may be sitting on surface hoar

A melt-freeze crust from early December is found around 80 to 180 cm deep in the snowpack. This crust may have surface hoar or sugary faceted grains sitting above it. This persistent weak layer is most prevalent in the north (e.g., Duffey Lake, Hurley).

Terrain and Travel

  • Be careful as you transition into wind affected terrain.
  • Be aware of the potential for large avalanches due to the presence of a deep persistent slab.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent southwest winds have created reactive wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A couple of problematic layers may be found around 80 to 180 cm deep primarily in the north of the region (e.g. Duffey, Hurley), including weak layers of surface hoar and faceted grains above a hard melt-freeze crust. Although the likelihood of triggering is reducing, the consequences of doing so would be high.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Jan 9th, 2021 4:00PM