Avalanche Forecast

Issued: Jan 6th, 2012 9:23AM

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

Jlammers, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Saturday: 6-8cm of snow arriving late in the day / moderate to strong southwest winds / freezing level at 1600m Sunday: 15-20cm of snow / strong southwest winds / freezing level climbing from 1600 to 2000m throughout the dayMonday: 15-20cm of snow / moderate southwest winds / freezing level lowering to 1000m throughout the day

Avalanche Summary

Widespread natural avalanche activity up to Size 3 was reported throughout the week. Fresh storm and wind slabs, as well as deeply buried persistent slabs remain sensitive to human triggers.

Snowpack Summary

Weaknesses within and under the 70-100+cm of storm snow will need some time to settle and strengthen. Persistent weaknesses remain a concern in the northern part of the region. Buried surface hoar on sheltered treeline slopes and below and facets with associated crusts in exposed treeline and alpine areas are probably down well over a metre in most places, and facets lurk near the base of the snowpack in shallow rocky areas. Wind-loading has resulted in highly variable slab thicknesses with the potential for fractures triggered in highly sensitive thin slab areas to propagate into highly destructive deep slab avalanches. Furthermore, weaknesses within the slab create the potential for step-down fractures.

Problems

Wind Slabs

Watch for sensitive wind slabs lurking below ridgecrests, behind terrain features and in cross-loaded gullies.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Storm Slabs

Watch for touchy storm slabs on steep unsupported terrain features.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 5

Persistent Slabs

Primarily a concern in the northern part of the region. Especially easy to trigger from thin slab areas, or from storm or wind slab avalanches stepping down to deeper weaknesses.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 6

Valid until: Jan 7th, 2012 8:00AM