Avalanche Forecast
Issued: Nov 28th, 2011 8:49AM
The alpine rating is Storm Slabs, Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Due to limited field observations
Weather Forecast
Light to moderate precipitation is expected over the region this evening accompanied by moderate northwesterly winds. Freezing levels will remain at valley bottom tonight through the later part of the week. Tuesday through Wednesday morning light-moderate snowfall amounts are forecast with winds continued from the northwest. Wednesday looks to become dry as a ridge moves over the Interior.
Avalanche Summary
In the Dogtooth range isolated natural avalanche activity was observed. These avalanches occurred from steep, rocky terrain at days end Sunday, up to size 1.5 due to rapid loading. I suspect this may have been the norm through the region as the freezing level was at 1800 meters and a surge of new snow and wind hammered through. This may be a good time to wait out the storm, let the new snow and the snowpack settle, and make observations from your local s mountains when the visibility improves.
Snowpack Summary
There is a lot of variation in the snowpack in this region. There is more snow in the Dogtooth area near Golden than there is further south near Invermere and Kimberley. There is probably quite a bit of snow to the west, in areas like the Bugaboos and Jumbo. We don't have any information yet from operators in the west of this region. In the early season we get most of our information from the Dogtooth. We know that there is a weak facetted layer at the ground that has been failing in the last week and resulting in very large avalanches. There has been 60-80 cms recently with strong winds and high freezing levels, creating a cohesive slab above the weak basal layer. In the higher alpine terrain there may be a rain crust from October. Areas in the region have received up to 35cm of new snow over the past 24hr period with switching winds from the northwest. This will create new storm snow and wind slab problems. Any deeper weak layers may continue to be a problem.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 29th, 2011 8:00AM