Avalanche Forecast

Issued: Dec 9th, 2016 4:40PM

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

Avalanche Canada jsmith, Avalanche Canada

Wind is the major weather factor to keep a close eye on this weekend. Even moderate wind speeds can quickly build fresh wind slabs reactive to human triggers.

Summary

Confidence

Moderate - Wind speed and direction is uncertain

Weather Forecast

Saturday: Mostly cloudy with isolated flurries / Light southwesterly winds / High of -15 C.Sunday: Cloudy with flurries / Light to moderate southwesterly winds / High of -17 C.Monday: Mix of sun and cloud / Light northwesterly winds / High of -16 C.

Avalanche Summary

No recent avalanche observations have been reported in this region.

Snowpack Summary

Up to 30 cm of recent storm snow has buried old snow surfaces including surface hoar and old, stiff wind slabs. The cold temperatures will have promoted surface faceting, which probably means the top layer of snow is soft in most places. Treeline snow depths around Elkford are only around 60 cm. I suspect they are slightly higher in places like the Flathead, but generally conditions are lean. Threshold snow depths for avalanches have been exceeded in the alpine and at treeline, but not below treeline. In shallow areas, the snowpack is most likely facetted (sugary) throughout, and any crusts have probably broken down already. In deeper areas, you can probably find the mid-November crust buried under half a metre or so of snow.

Problems

Wind Slabs

An icon showing Wind Slabs
Lingering wind slabs formed last weekend could still be reactive to human triggers in isolated terrain features. Changing wind directions may also reverse load normally windward slopes and catch you by surprise.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 10th, 2016 2:00PM