Avalanche Forecast

Issued: Feb 22nd, 2015 4:00PM

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

Aaron Beardmore, Parks Canada

Banff Yoho Kootenay.

Forecasters experienced a large whumph above Pika Flats in the Lake Louise back-country today. This emphasizes that there is still potential for human triggering, especially in shallow areas.

Summary

Weather Forecast

Light wind, clear skies and little to no precipitation are expected over the next couple of days. The main concern will be solar radiation on south aspects. Although the solar effect may not change the danger rating, it could induce moist avalanches on a local level.

Snowpack Summary

A well settled upper snowpack with highly variable depths sits over the ever present weak facets and depth hoar in the bottom half of the snowpack. Colder temperatures have helped the slab bridge over the weaker base. Expect to find wind slabs in lee areas in the alpine.

Avalanche Summary

No new avalanches were observed or reported today.

Confidence

Problems

Deep Persistent Slabs

The lower half of the snowpack is weak due to the presence of basal depth hoar and facet layers. Natural activity has ceased but skier triggering is still possible, especially in shallow areas and places where the snowpack is unevenly distributed.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

Be cautious near ridge-crests and in lee areas. These seem to be isolated to the Icefields Parkway region.

Be careful with wind loaded pockets

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Feb 23rd, 2015 4:00PM