Avalanche Forecast

Issued: Feb 13th, 2013 8:14AM

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

Alberta Parks jeremy.mackenzie, Alberta Parks

Recent snow and extreme NW winds are creating storm slabs that are sensitive to human triggering. This new snow has buried a wide variety of layers that will give inconsistent shear results. Evaluate the snowpack carefully.

Summary

Confidence

Fair - Due to limited field observations

Weather Forecast

NW winds will continue on Thursday, and will increase in speed through the day. No precipitation is expected and alpine temperatures will range from -18 to -6 degrees.

Avalanche Summary

Nothing new, but observations were limited.

Snowpack Summary

Up to 12cm of new snow at treeline in the past 24hrs. Storm slab development in alpine and treeline areas with slabs between 20 and 30cm deep. Previously formed hard slabs that are widespread on NW through S aspects are now well hidden under the new snow. Weak and facetted snowpack remains at lower altitudes.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slab development is on-going on lee and cross loaded features in alpine and treeline areas. With the extreme NW winds these slabs extend far downslope on E and S aspects and will be sensitive to human triggering.
Avoid freshly wind loaded features.>Avoid lee and cross-loaded terrain near ridge crests.>Be careful with wind loaded pockets while approaching and climbing ice routes.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Wind Slabs

An icon showing Wind Slabs
Previously formedĀ  hard wind slabs are now buried 10 to 40cm deep in alpine and treeline areas. Shallow snowpack areas and steep convex features are potential triggering spots for this buried wind slab.
Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Valid until: Feb 14th, 2013 2:00PM