Avalanche Forecast

Issued: Jan 22nd, 2013 8:44AM

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

pgoddard, Avalanche Canada

Northwest Inland.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain for the entire period

Weather Forecast

Wednesday: Moderate to strong SW wind.Â Alpine temperature near -5. Moderate snow.Thursday: Strong S to SW winds. Alpine temperature near -5. Light snow, becoming moderate late in the day.Friday: Strong SW winds. Alpine temperature near -5. Light to moderate snow.

Avalanche Summary

On Friday, hard wind slabs failed naturally in the north of the region on northeast and east aspects. In isolated occurrences, these triggered full-depth avalanches that ran on basal facets. No avalanches have been reported since then.

Snowpack Summary

The current medley of snow surfaces includes hard and soft wind slabs, scoured slopes, blue ice and thin melt-freeze crusts. New snow may bond poorly to some of these surfaces, especially where surface hoar sits on a hard crust. Surface hoar layers buried in the upper snowpack are patchy in their distribution. Recent snowpack tests gave moderate to hard, resistant results on one of these layers near Smithers. An otherwise strong mid-pack overlies a weak base layer of facets/depth hoar and the remnants of a crust. The snowpack depth is around 100 cm at treeline.

Problems

Storm Slabs

Incoming snow may bond poorly to old surfaces. New wind slabs are also likely to develop during the next few days.

Avoid freshly wind loaded features.>Be cautious of sluffing in steep terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Deep Persistent Slabs

A deeply buried facet/crust weakness exists near the base of the snowpack. This layer could be triggered by large loads such as a cornice collapse or from a thin-spot trigger point.

Avoid convexities or areas with a thin or variable snowpack.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 6

Valid until: Jan 23rd, 2013 2:00PM