Avalanche Forecast
Issued: Dec 4th, 2019 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
william lawson,
Parks Canada
Higher then forecasted snow fall amounts and strong winds have resulted in a heightened avalanche danger for the region.
Summary
Weather Forecast
Snow ending Wednesday with a short reprieve Thursday before the next system hits Friday which could bring an additional 20cm to the region. Temperatures will rapidly cool Thursday with a forecasted low of -20. This will be short lived, as the next wave of precipe moves in freezing levels could climb up to 1400m.
Snowpack Summary
20 to 30cm of new snow accompanied by moderate to strong SW winds have created fresh wind slabs on lees slopes at treeline and above. The midpack consists of 25-35 cm of facetted snow overtop of the Nov 8 crust. The lower snowpack consists of facets and depth hoar. Snowpack depths at treeline vary from 60-100 cm with up to 140 cm in lee areas
Avalanche Summary
Reactive wind slabs on alpine and treeline lee slopes are producing avalanches to size 2 in the region. Little evidence of these slabs stepping down to deeper instability has been observed, though with the current snowpack structure it is something to consider. We will likely find more evidence of an avalanches cycle Thursday as things clear up.
Confidence
Problems
Wind Slabs
20-30 cm of recent storm snow accompanied by strong SW winds have created widespread wind slabs in alpine and tree-line regions. Slabs of 50cm thick have been reactive to skier traffic.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 5th, 2019 4:00PM
