Avalanche Forecast

Issued: Jan 9th, 2013 8:36AM

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

pgoddard, Avalanche Canada

Cariboos.

Conditions are variable across the region.

Summary

Confidence

Fair - Due to variable snowpack conditions

Weather Forecast

Thursday: Light N wind. Alpine temperature near -11. No precipitation.Friday: Light NW wind. Alpine temperature near -13. No precipitation.Saturday:Light W wind. Alpine temperature near -16. Light snow.

Avalanche Summary

A natural cycle of size 1-1.5 storm slabs was observed on Monday and Tuesday. Skiers also triggered small avalanches, failing on buried surface hoar or facets. I expect a more widespread avalanche cycle occurred on Wednesday.

Snowpack Summary

New snow has developed into slabs, with a weak bond to old snow surfaces including surface hoar (found at and below treeline) and facets. Variable amounts of snow (25-90 cm) have fallen across the region, meaning the avalanche danger is likely to be different from place to place. In heaviest-affected areas, there is the potential for deep and destructive storm snow avalanches. Strong winds have left widespread wind slabs in the lee of terrain breaks such as ridges and ribs. In areas sheltered from the wind, fast-moving sluff could throw you off your feet or carry you into a terrain trap. A strong mid-pack overlies a weak facet/crust layer near the base of the snowpack.

Problems

Wind Slabs

Strong winds have shifted snow into wind slabs which could fail naturally, or with the additional weight of a person or snowmobile.

Stay off recent wind loaded areas until the slope has had a chance to stabilize.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 6

Storm Slabs

Storm snow has a weak interface with the old snow surface. This will take some time to settle and bond, even after the weather improves.

Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Be cautious of sluffing in steep terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 5

Valid until: Jan 10th, 2013 2:00PM