Avalanche Forecast

Issued: Jan 7th, 2012 9:19AM

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

Jlammers, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

Sunday: Snowfall become heavy in the afternoon, Forecast amounts to 20cm / Strong southwest winds / Freezing levels rising to 1800m Monday: Continued moderate to heavy snowfall tapering off in the afternoon / Moderate to strong southwest winds / Freezing levels dropping from 1400m to 700m as snowfall tapers off Tuesday: Clear skies with no precipitation / Winds switching to light and northerly / Freezing level dropping to surface

Avalanche Summary

No new avalanche activity reported.

Snowpack Summary

Weaknesses within and under the 70-100+cm of storm snow will need some time to settle and fully 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.Expect further wind slab and storm slab development with forecast weather

Problems

Wind Slabs

With forecast weather, expect stiff windslabs to develop on lee and cross-loaded terrain at treeline and in the alpine

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 5

Storm Slabs

Forecast snowfall will add to the current storm slab instability.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 5

Persistent Slabs

Primarily a concern in the northern part of the region. Triggering is more likely from thin slab areas (ie: moraines or cross-loaded terrain), or from storm or wind slab avalanches stepping down to deeper weaknesses.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 6

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