Avalanche Forecast

Issued: Dec 21st, 2011 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.

Brad White, Parks Canada

Banff Yoho Kootenay.

Deep full depth slabs can still be triggered with explosives and also could be human triggered from a thin spot or rocky area. Conservative route selection will give good ski quality without excessive exposure. JBW

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Problems

Wind Slabs

There are some small fresh wind slabs and ripe cornices that could be triggered on lee features. In some cases the slabs may be enough to trigger the deep basal instability.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

Avalanche control on the Sunshine road today produced some full depth slabs as thick as 1.5 metres that were running fast and quite far. These avalanches failed on the ground and October crust and show that human triggering is still a possibity.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Dec 22nd, 2011 4:00PM