Avalanche Forecast

Issued: Feb 3rd, 2012 9:30AM

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.

triley, Avalanche Canada

Cariboos.

Summary

Confidence

Good - -1

Weather Forecast

Warm daytime temperatures and freezing down to the valley bottoms is expected over the weekend. The freezing level is forecast to rise to about 1700 metres on both Saturday and Sunday. Expect mostly sunny skies and light south to southeast winds through the forecast period.

Avalanche Summary

Large looming cornices are likely to start falling off with warm temperatures and solar radiation. Large slab avalanches that propagate across entire slopes are possible, especially with heavy triggers such as step-down avalanches, cliff-drops, and cornice drops.

Snowpack Summary

Total snowpack depths are well above average or even new record depths for this time of year. Weaknesses within the upper snowpack and the facets and surface hoar buried mid-January, create the potential for large step-down avalanches, but things seem to be settling rapidly.Snowpack tests on the mid-January facets down 80-150cm consistently produce sudden fractures and this weakness seems to be particularly touchy below 1500m where it is shallower and sits on a crust. Weak wind slabs and large fragile cornices are lurking in exposed lee and cross-loaded terrain.

Problems

Cornices

Large cornices are looming over many slopes. Warm temperatures and solar radiation will likely weaken them, and a falling chunk could trigger an avalanche on the slope below.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 4

Wind Slabs

Wind slabs are generally lurking below ridge crests, behind terrain features and in cross-loaded gullies. They can fail as very large, destructive avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 6

Storm Slabs

Large storm slab avalanches have been occurring for the past week and are expected to remain sensitive to triggers for the forecast period.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Feb 4th, 2012 3:00AM