Avalanche Forecast

Issued: Mar 1st, 2013 9:25AM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Storm Slabs, Cornices and Loose Wet.

Avalanche Canada swerner, Avalanche Canada

Summary

Confidence

Fair - Intensity of incoming weather is uncertain for the entire period

Weather Forecast

Saturday: As the strong Pacific front starts to push northward, precipitation will ease off to light amounts during the day and moderate amounts developing in the evening. Strong ridgetop winds becoming moderate from the West and freezing levels rising to 2200 m falling to valley bottom overnight.Sunday: Light-moderate precipitation accompanied by moderate ridgetop winds from the NW. Alpine temperatures near -8 and freezing levels at valley bottom.Monday: No significant precipitation expected with ridgetop winds blowing light form the SW. Alpine temperatures near -5, and freezing levels hovering around 1400 m in the afternoon.

Avalanche Summary

On Thursday reports indicate a size 2 skier triggered avalanche off of a windloaded ridgeline feature running on a layer of facetted crystals. A subsequent size 1 avalanche was triggered nearby. This was in the Three Sisters area just north of Fernie.On Friday loose wet avalanches occurred up to size 1.5 from steep terrain features below treeline.

Snowpack Summary

About 30cm of storm snow has fallen with generally lower amounts in the North Elk and Crowsnest areas. The new snow has been shifted onto lee slopes by strong west and southwest winds creating wind slabs. With additional forecast snow and strong winds, storm slabs, cornices and wind slabs will continue to build.Mid and lower snowpack layers are generally well settled.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slabs will continue to build through the weekend. Recent strong winds have created slabs in the lee of terrain features and are likely triggered by the weight of a person.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 5

Cornices

An icon showing Cornices
Cornice fall may act as a trigger for slabs on slopes below.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Loose Wet

An icon showing Loose Wet
Continued precipitation and rising freezing levels may cause loose wet avalanche activity from steeper terrain features. Pin-wheeling and moist snow surfaces are the initial indicators.
Watch for wet loose or slab activity with forecast rain and/or warm temperatures, especially where terrain traps exist below.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 2nd, 2013 2:00PM