Avalanche Forecast

Issued: Dec 29th, 2011 4:00PM

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

chris gooliaff, Parks Canada

Banff Yoho Kootenay.

Another storm on Friday should deliver 15-20cm of snow, along with strong SW winds. Numerous natural avalanches were observed today in the alpine, including a large size 3 over the ice climb Bourgeau Left. These will continue with additional snow.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Problems

Wind Slabs

In most areas, storm snow amounts are now about 30 to 50 cm. SW winds have created soft slabs up to 60 cm deep. These are touchy and are running long distances. Avalanche control on Mt Whymper produced avalanches to size 3 running to valley-bottom.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

This layer seems to be activating with the additional load. Avalanche control on the Lake Louise Ski Hill saw slabs stepping down into the facets in shallow, rocky areas. A large windslab release has the potential to step down into these facets.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Storm Slabs

Distribution of this layer is spotty but mostly on the west side of the Divide.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 30th, 2011 4:00PM