Avalanche Forecast

Issued: Dec 13th, 2011 4:15PM

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

Jon Stuart-Smith, Parks Canada

Waterton Lakes.

Strong winds have started to build the storm snow from Sunday into wind slabs. Sheltered areas best bet for some turns. Strong winds still forecast for Tue night but should die down by Wed. Forecast uncertain for snow on Thur. Snow @ L. Prairie 75cm.

Summary

Problems

Wind Slabs

Strong winds are building the storm snow from Sunday into slabs. It was easy to trigger small wind slabs in steep terrain on Forum ridge on Tuesday. The avalanches were small but if you were in the wrong place you could get knocked over and buried.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

The basal weakness is bridged with dense snow in most locations, and is showing signs of strengthening. Warm temps last week and increased snow depth should help this process but the potential for large, destructive avalanches remains a concern.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Dec 16th, 2011 4:00PM