Avalanche Forecast

Issued: Feb 3rd, 2012 11:06AM

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

jfloyer, Avalanche Canada

Northwest Inland.

Warm alpine temperatures may result in unexpected large avalanches, especially on south-facing terrain.

Summary

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Saturday and Sunday: Dry or very light flurries, with alpine temperatures around -2C. Winds expected to be light southwesterly rising to moderate southeasterly. Monday: Clear with sunny spells. Temperatures below freezing at low elevations but alpine areas may see inversion conditions that will elevate temperatures to near zero.

Avalanche Summary

Small cornice releases that have so far not released slabs on slopes below were reported from Friday. A large nautral avalanche (size 3) was reported from the Hankin-Evelyn from last weekend on a NW aspect.

Snowpack Summary

I suspect pockets of wind slab behind ridges & ribs at alpine and treeline elevations. I also suspect storm slabs on steeper terrain, unsupported slopes, or convex rolls. Deeper in the snowpack is a layer of facets (sugary snow) which formed during the cold mid-January drought. The combination of newer, warmer, cohesive snow above a thin, weak, rotten snowpack is a bad combination.

Problems

Cornices

Cornices are expected to become unstable with anticipated warm alpine temperatures.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

2 - 6

Wind Slabs

Below ridge crests, behind terrain features and in cross-loaded gullies.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 5

Storm Slabs

Facets down 40-60cm may take some time to gain strength. Watch steep slopes, convex rolls, and unsupported slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Feb 5th, 2012 3:00AM