Avalanche Forecast

Issued: Nov 25th, 2011 4:00PM

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

Snow Safety, Parks Canada

Banff Yoho Kootenay.

Unusually dangerous avalanche conditions exist. Another storm Saturday through Sunday may produce 30+ cm of snow with strong Westerly winds, further deteriorating conditions. Backcountry travel in avalanche terrain is not advised this weekend. SH

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

on Saturday

Problems

Deep Persistent Slabs

Up to 45cm of snow deposited last Wed. formed wind slabs 60-100cm deep. This has overloaded the weak basal depth hoar and facets. Lake Louise and Sunshine ski areas reported widespread activity up to 2.5 today from explosive control, some 200m wide.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 3

Wind Slabs

As new snow accumulates this weekend, expect rapid wind slab formation, which will continue to overload the basal facets, increasing natural activity and the potential for human triggered avalanches.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 3

Valid until: Nov 26th, 2011 4:00PM