Avalanche Forecast

Issued: Jan 27th, 2012 11:22AM

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

pgoddard, Avalanche Canada

Cariboos.

Summary

Confidence

Fair - Timing of incoming weather is uncertain on Saturday

Weather Forecast

Saturday: Moderate to heavy precipitation. Freezing level rising through the day to around 1300m. Strong to gale south-westerly winds at ridge top. Sunday: Light to moderate snow continues. Freezing level staying near 1200m. Strong westerly winds.Monday: A break from heavy snow, although light snow is possible, especially on western slopes. Freezing level falling back to valley floor.

Avalanche Summary

On Thursday, a skier remotely triggered a size 1.5 slab on a convex feature. It failed on facets beneath the storm snow. On Wednesday, three size 3.5 natural avalanches ran full path. A few other natural avalanches, up to size 2, were observed in steep lee (wind-loaded) terrain. Whumphing was observed below treeline.

Snowpack Summary

Up to 1m of snow has fallen since Monday. Strong winds have created hard slabs, soft slabs and fragile cornices. Snowpack tests give easy to moderate results on several layers in the upper snowpack. Key concerns as further snow builds this weekend include a weak facet layer that was created during the brutal cold snap in mid-January and a buried crust which is found below treeline.

Problems

Wind Slabs

Wind slabs continue to build behind ridges and terrain breaks. Areas that avalanched earlier this week may re-load as the storm continues. Cornices are looming above many slopes, which could act as a trigger for deep avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

2 - 7

Storm Slabs

Storm slabs continue to build above buried weak layers. Warming and snowfall this weekend will increase the storm slab problem.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 5

Valid until: Jan 28th, 2012 8:00AM