Avalanche Forecast

Issued: Mar 25th, 2012 10:33AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Cornices, Deep Persistent Slabs and Loose Wet.

jlammers, Avalanche Canada

Cariboos.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

Monday: Mostly clear with increased cloud late in the day - light and variable winds - freezing level at 1600m Tuesday: very light snowfall - moderate - southwest winds - freezing level at 1500m Wednesday: light snowfall - moderate southwest winds - freezing level at 1500m

Avalanche Summary

3 size 3 natural avalanches were observed in steep, rocky, unsupported terrain. They occurred between 2000-2800m on north to east aspects and are suspected to have run on the February persistent weak layer. Solar radiation may still be an issue on Monday. If this is the case there will be an elevated chance of avalanche activity.

Snowpack Summary

Recently formed wind slabs exist in the alpine and at treeline. Solar radiation has led to moist surfaces on sun exposed slopes with good crust recovery developing at night. Cornices have grown large and unstable. A consolidated deep slab overlies weak surfaces that formed in early February. Now 1-2 m below the surface, these weaknesses include surface hoar, facets or crusts. Operators continue to express concern about the potential for deep and destructive releases at this interface.

Problems

Cornices

Large cornices exist and are becoming more likely to fail, especially when solar radiation is strong. A cornice fall could trigger a very large avalanche on the slope below. Wind slabs also exist at higher elevations.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 5

Deep Persistent Slabs

A weak interface down 1-2m remains concerning. While avalanches on this layer have become less frequent, those that do release are very large and destructive. Solar warming may spark renewed activity.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

3 - 7

Loose Wet

If solar radiation is strong loose wet avalanches will occur, especially on steep, rocky, south-facing terrain.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 26th, 2012 9:00AM