Avalanche Forecast

Issued: Dec 15th, 2016 3:53PM

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

Avalanche Canada swerner, Avalanche Canada

Forecast strong winds will elevate the avalanche danger through the weekend.

Summary

Confidence

High - The weather pattern is stable

Weather Forecast

Mainly clear skies and cold temperatures, the coldest on Friday, as low as minus 25 as the arctic high continues to dominate the province. By the weekend the weather pattern will shift as the high moves to the southeast allowing several weak Pacific frontal systems to make their way to the coast. A stronger system should hit the coastal regions by Sunday, moving into the Interior Monday bringing cloudy skies, snow and strong winds at upper elevations.

Avalanche Summary

On Wednesday, a large size 3 glide crack release was reported from a steep south face at 2500 m. Besides that, natural avalanche activity has been far and few with some sluffing from steep or extreme terrain. Isolated wind slabs continue to be reactive to light loads (people) on leeward slopes, mostly size 1-2. With increased winds over the weekend, the avalanche danger may rise with new wind slab problems being the primary focus.

Snowpack Summary

Due to cold and clear conditions a variety of surface snow exists from faceted (sugary) crystals to surface hoar crystals up to 8 mm in size. Variable wind effect has created wind slabs in isolated areas at upper elevations. Watch for a recently buried layer of surface hoar down 30-40cm that may develop a poor bonding layer. The depth of the mid-November crust is also variable across the region. Reports have the crust down between 100-200 cm and snowpack tests have produced a variety of results from moderate and sudden to hard and resistant, and in some cases no result. If you dig down to the crust, watch for facets developing above and/or below. This may provide a weak layer above a smooth sliding surface in the future.

Problems

Wind Slabs

An icon showing Wind Slabs
Forecast winds are increasing in strength over the weekend and may build new wind slabs at treeline and in the alpine. Watch for conditions that change with aspect and elevation.
Be cautious of sluffing in steep terrain.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 16th, 2016 2:00PM