Avalanche Forecast

Issued: Jan 21st, 2012 10:15AM

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

Avalanche Canada jlammers, Avalanche Canada

Summary

Confidence

Fair - Due to variable snopack conditions

Weather Forecast

Sunday: light snowfall / moderate to strong westerly winds / freezing level at surfaceMonday: Light snowfall / moderate to strong southwest winds / freezing level at surfaceTuesday: moderate snowfall / strong southwest winds / freezing level at surface

Avalanche Summary

No new avalanche observations to report. Avalanche activity can be expected in the wake of Saturday's weather.

Snowpack Summary

Over the week 40-60cm of snow formed soft slabs over a crust/facet/surface hoar combo. Snowfall, wind and warming on late Friday/Saturday have created a more reactive storm slab problem as dense snow now over-rides colder, lighter snow where weaknesses are more likely to endure. Deeper in the snowpack, a surface hoar layer buried in early December remains a concern, as avalanches triggered on this layer would be destructive. However, information is limited about its current reactivity. From preliminary observations, the rapid storm snow load over the past week did not cause any releases on this layer. Basal facets also exist in many parts of the region.Facets sandwiched between two firm layers in the top metre of the snowpack are being monitored in the south-east.

Problems

Storm Slabs

An icon showing Storm Slabs
A classic recipe for storm slabs has evolved: moderate snowfall with rising temperatures landing on loose dry snow. Watch for storm snow avalanches, especially in steep or convex terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 5

Wind Slabs

An icon showing Wind Slabs
Watch for wind slabs on lee features at treeline and in the alpine.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Jan 22nd, 2012 8:00AM