Avalanche Forecast

Issued: Apr 11th, 2015 4:20PM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Wind Slabs and Cornices.

conrad janzen, Parks Canada

Banff Yoho Kootenay.

Good skiing on all aspects with 10-25cm of new snow. Travel conditions remain excellent, but the hazard has risen with the new snow and strong gusty winds. Use caution in steep terrain and wind loaded areas. See more Spring Conditions details here.

Summary

Weather Forecast

Continued light snow with cool temperatures and gusty West winds are forecast for Sunday. Additional accumulations are forecast to be in the 5-10cm range at tree line. Monday remains cool and cloudy with a trace of new snow, freezing levels rising to 1900m and moderate West winds.

Snowpack Summary

10-25cm of new snow on Saturday with gusty SW winds has created wind slabs in lee areas above treeline. The new snow sits on a firm crust on solar aspects up to ridge crests and up to 2300m on N aspects. This buried crust provides a bridge over the facets which remain dormant at the base of the snowpack but are the main weakness in the snowpack.

Avalanche Summary

One small skier accidental on a N aspect on Mt Bell on Saturday in the new snow. Ski cutting produced numerous small wind slabs at the local ski areas. One recent size 2.5 failing on the basal facets in the Observation Peak area in the past 48hrs. Several recent cornice failures pulling out small slabs on the basal facets have been reported.

Confidence

Problems

Wind Slabs

Wind slabs have formed in lee areas above treeline up to 40cm thick. These are reactive to skier traffic and have been failing naturally in some locations. Expect sluffing in any steep terrain as well.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Be cautious of sluffing in steep terrain.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

There have been many reports of cornice chunks falling off of ridge crests which may be big enough a load to trigger an avalanche on the basal facets, or be enough mass to be a hazard themselves.

Stay well back from cornices.Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 12th, 2015 4:00PM