Avalanche Forecast

Issued: Dec 22nd, 2016 4:33PM

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

Avalanche Canada mbender, Avalanche Canada

As this past week's storm snow continues to settle it will still be important to evaluate the bond between the old snow surface and the new snow. There is still potential for a weak sliding layer in isolated sheltered areas.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Friday

Weather Forecast

Friday: Scattered flurries / Light east wind / Alpine temperature -4Saturday: Flurries, accumulation 5-10cm / Light east wind / Alpine temperature -10Sunday: Mix of sun and cloud / Light west wind / Alpine temperature -13

Avalanche Summary

A few wind slab avalanches (mostly in the size 2 range), were observed failing with explosives on Tuesday and Wednesday in the alpine. There is a bit of uncertainty regarding how the new snow will bond to old surfaces which formed during last week's cold snap. Given this, there is still potential for skier and rider triggering in sheltered areas where buried surface hoar may exist or in wind exposed terrain where wind slabs maybe sitting on facets.

Snowpack Summary

Since Sunday up to 60cm of low-density snow has fallen with the highest amounts accumulating in the Lizard Range. Strong winds and slight warming have added cohesion to the new snow and reactive wind slabs exist in exposed terrain. The new snow buries a variable surface that developed over the last week of cold, dry, and windy conditions. This interface consists of scoured surfaces and wind slabs in wind exposed terrain, widespread faceting of the upper snowpack, and surface hoar up to 20mm in sheltered areas. In sheltered areas, you may find another layer of surface hoar in the mid to upper snowpack which was buried around December 10. The mid pack is generally well settled. The thick crust from mid-November is near the bottom of the snowpack and reports suggest that the crust is currently well bonded to the surrounding snow.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind and warming have added cohesion to the recent storm snow. Use extra caution in steeper, wind-exposed terrain.
Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious as you transition into wind affected terrain.Watch for signs of instability such as whumpfing, or cracking.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 23rd, 2016 2:00PM