Avalanche Forecast

Issued: Dec 21st, 2012 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs.

snow safety, Parks Canada

Banff Yoho Kootenay.

Excellent ski quality in sheltered features. Watch for new wind slabs at treeline and above. SH

Summary

Weather Forecast

Trace to 5cm snow Saturday with L South winds in the alpine and continued cool temperatures. Sunday may see some increased winds and light snow accumulations.

Snowpack Summary

New wind slabs 20-50cm thick (4finger-1finger stiffness) on wind exposed treeline and alpine lee slopes formed by SW winds in last 48 hours. Mainly sitting on a thin layer of facets but isolated in nature. Well settled midpack in thicker snowpack areas, Nov 6 crust facetting in thinner areas. Low density powder below treeline.

Avalanche Summary

2 size 3 naturals on the N. face of Mt. Victoria within the last 24 hours, initiating at 3000-3300m It is suspected wind loading caused the snowpack to fail on glacial ice or old firn snow, No other avalanches of this magnitude observed or reported. Size 1-1.5 skier controlled avalanches reported at Sunshine ski area limited to ridge crests.

Confidence

on Saturday

Problems

Wind Slabs

Wind slabs 20-50cm thick in wind exposed areas from recent SW winds. These seem to be isolated to the lees of terrain features and ridge crests. Reports are finding these wind slabs to be sitting on a thin layer of facets formed in early Dec.

Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Dec 22nd, 2012 4:00PM