Avalanche Forecast

Issued: Mar 8th, 2012 4:00PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

Strong to extreme W. winds, freezing levels to 2000m and up to 10cm of snow (drizzle at lower elevations) will keep the hazard elevated on Friday. A few large natural avalanches were observed today, and it still feels spooky out there. SH

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Forecast snowfall amounts are uncertain on Friday

Problems

Persistent Slabs

The Valentine surface hoar down up to 90cm is overlain by a stiff slab and remains very sensitive to triggers. Natural activity has slowed somewhat,but a few solar releases (Urs Hole) to size 3 were seen. Some slopes have reloaded over the last day.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 4

Wind Slabs

Strong NW winds over the last 24-hours have created windslab conditions in open areas at higher elevations. These have been reported to be fairly stubborn to trigger today at Sunshine Village,

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

The deep facets in the Rockies snowpack are awake again. These have mainly been observed on bigger features where the weight of the initial avalanche triggers the basal depth hoar, causing very large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Mar 9th, 2012 4:00PM