Avalanche Forecast

Issued: Mar 7th, 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.

The widespread large avalanche cycle continues. Large avalanches are expected again on Thursday with the weather forecast of warming and strong winds. More snow again for Friday will keep the avalanche danger HIGH for the rest of the week. GS

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Due to the number and quality of field observations

Problems

Persistent Slabs

The Valentine surface hoar down 75 cm is overlain by a stiff slab and remains very sensitive to triggers. This problem is actively producing large avalanches in many locations and will remain so for the forecast period. Avoid all steep open terrain.

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. With 80cm of recent storm snow available for transport, expect deep slabs in leeward areas.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

The deep facets in the Rockies snowpack are awake again, and are responsible for numerous size 3 and 4 avalanches in the last 48-hours. Avalanches starting in the upper snowpack are stepping down into the base of the snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Mar 8th, 2012 4:00PM