Avalanche Forecast

Issued: Jan 9th, 2015 4:00PM

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

patrick jerome, Parks Canada

Banff Yoho Kootenay.

The last storm has deposited 15-20 cm's of snow on the Dec 18th interface which is slowly becoming a stiffer slab, be cautious at treeline and in the alpine. This layer and the basal facets remain persistent issues with our snowpack in the Rockies.

Summary

Weather Forecast

The weather outlook for the weekend is very light precipitation and rising freezing levels on Saturday evening and then temperatures cool off on Sunday and into next week.Â The predominant pattern will be high pressure with little precipitation forecast until next weekend at the earliest.

Snowpack Summary

Windslabs on facets and crust can be found on most exposed solar aspects. Pay particular attention to lee slabs on north and east aspects near ridge top features, the winds from last night have created a measurable amount of tension in these slabs which if initiated, have the capacity to step into the deeper basal facets creating large avalanches.

Avalanche Summary

Avalanche control a few days ago produced a few large avalanches and some continued natural activity yesterday. Today's activity near Lake Louise included avalanches in the size 2 to size 3 range.Â These avalanches are being initiated at the Dec 18th interface and in steep, large scale terrain features are stepping down to ground.

Confidence

Due to the number and quality of field observations on Saturday

Problems

Wind Slabs

Caution in lee and cross-loaded terrain near ridge crests.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Jan 10th, 2015 4:00PM