Avalanche Forecast

Issued: Dec 22nd, 2016 4:30PM

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

mbender, Avalanche Canada

Kootenay Boundary.

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 Saturday

Weather Forecast

Friday: Flurries, accumulation 5-10cm / Light east wind / Alpine temperature -7Saturday: Flurries, accumulation 5-10cm/ Light east wind / Alpine temperature -7Sunday: Mainly cloudy / Light west wind / Alpine temperature -9

Avalanche Summary

Recent reports in the past few days indicate a few wind slabs avalanches triggered from explosives control running on the storm/old snow interface to size 2 at tree line and above.

Snowpack Summary

20-40 cm of new snow from earlier in the week has buried old wind slabs, facets and surface hoar. There is a bit of uncertainty regarding how the new snow is bonding to old surfaces which formed during last week's cold clear period. Moderate to strong winds have loaded leeward features with wind slabs. A widespread crust that was buried in November is typically down 80-100cm. Recent tests show variable results with this persistent weakness. Some show results as hard and resistant and other show it may have the propensity to propagate if triggered from thin rocky areas.

Problems

Wind Slabs

Moderate to strong southwest winds continue to create slabs in the lee of terrain features

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for signs of instability such as whumpfing, or cracking. Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

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