Avalanche Forecast
Issued: Dec 11th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs.
mark herbison,
The recent storm snow is slowly faceting out, which is prolonging the high ski quality.
Before slashing into a committing line, have a dig to test the bond between the new and old snow layers. Expect sluff to run fast and far.
Summary
Weather Forecast
A ridge of high pressure remains. Sunny skies, light winds and cool temps will continue over the weekend.
Snowpack Summary
20-40 cm of low density snow sits on the Dec 7th layer of sun crust, facets or surface hoar depending on your location. This snow came with minimal wind and is less reactive than we had thought it might be. The Nov. 5th crust / facet layer persists at the bottom of the snowpack. Snowpack depths are 90-160cm at tree line.
Avalanche Summary
Solar triggered loose dry, size 1-1.5 out of steep rocky terrain were observed today throughout the region. A size 2 slab from the past 24hrs was reported on the N aspect of Mt. Ball.
On Thursday Lake Louise ski area triggered a size 2.5 with explosives, 60-100cm deep and ran for 200m. No notable explosive controlled avalanches on Friday.
Confidence
Problems
Deep Persistent Slabs
The Nov 5 crust has facets above and below it, and exists up to 2500m on shady aspects and higher on solar aspects. We haven't seen any activity on this layer since the storm, but the new load may have made it more reactive in some areas.
- Be aware of thin areas that may propogate to deeper instabilites.
- Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 12th, 2020 4:00PM
