Avalanche Forecast

Issued: Dec 15th, 2016 3:39PM

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

cam_c, Avalanche Canada

Kootenay Boundary.

Fresh and touchy wind slabs are building in unusual places. Use caution as you transition into exposed terrain.

Summary

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

On Friday expect a mix of sun and cloud with light to moderate northerly winds and alpine temperatures in the -15 to -20 range. Mainly cloudy for Saturday with moderate to strong northwesterly winds and alpine temperatures around -15. Sunday should also be mainly cloudy with a chance of flurries late in the day. Ridgetop winds are expected to increase to strong westerlies and alpine temperatures increasing to -10.

Avalanche Summary

No new avalanches were reported on Wednesday. Reports from Tuesday are limited to natural and rider-triggered sluffs up to Size 1.5. Reports from Monday include sensitive ridgetop wind slabs with numerous Size 1's with ski cuts. Elsewhere, explosives control produced limited results with a few Size 2 slabs that likely ran on the late November rain crust.

Snowpack Summary

Around 30cm of faceted powder overlies the facets and surface hoar that was buried last weekend. Variable light to moderate winds have loaded immediate leeward features with touchy wind slabs. A widespread crust that was buried in November is typically down 80-100cm. Recent tests show this persistent weakness has the propensity to propagate large avalanches if triggered, from thin rocky areas, for instance.

Problems

Wind Slabs

Fresh wind slabs on the downwind side of ridge crests and terrain features are highly sensitive to human triggers. Expect to find these deep pillows of wind-transported snow in unusual places thanks to recent northerly winds.

On steep slopes, pull over periodically or cut into a new line to manage sluffing.Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

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