Avalanche Forecast

Issued: Nov 22nd, 2011 4:00PM

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

jon stuart-smith, Parks Canada

Waterton Lakes.

Danger rating has risen with the moist system that has hit the area. Accumulation could be 30 to 40 cm by the end of the storm. This could overload the shallow early season snowpack with weak layers at the base.

Summary

Problems

Storm Slabs

The weak layers at that base of the snow pack are getting over loaded with moist, dense and heavy snow. Another 15 to 20 cm are forecast for the next 48 hours. Slab avalanches are likely, especially where the basal crust is prevalent, above 1900m.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Strong southwest winds have redistributed the storm snow from the weekend. These slabs are sitting on weak layers at the base of the snowpack. They will become more touchy as the slab thickens with the strong winds and new snow.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Nov 25th, 2011 4:00PM