Avalanche Forecast

Issued: Feb 23rd, 2013 8:11AM

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.

mike.koppang, Alberta Parks

Kananaskis.

The slow increase in avalanche hazard continues. Not a huge increase in the hazard, but we are still expecting things to get worse before they get better. Today's field trip noted especially variable conditions. Choose terrain carefully. MM

Summary

Confidence

Good

Weather Forecast

We'll be coasting for another day on the same weather pattern as the last 24hrs. Very light precip and sustained westerly winds in the alpine. Overnight Sunday another wave of precip will move through. By Tuesday morning up to 14cm are expected. As this wave wears out, the winds will shift to the north, but decrease in speed.

Avalanche Summary

Lots of loose dry out of extreme alpine terrain. These have run fast and entrained a fair amount of snow. This cycle seems to over. Isolated windslabs have also pulled out. They are generally small and isolated to ridge crests in the alpine.

Snowpack Summary

Up to 15 cm of new snow has come in a series of weak storms in the last 48hrs. Strong winds accompanied the snow. There are windslabs building at TL & ALP, on all N to E asp. These new slabs are the latest in a series of slab building events. There are now up to 4 different slabs lurking beneath the surface. These sit on the hardslab that was created weeks ago. This layer is the one we are watching closely. Cornices have been growing lately.

Problems

Storm Slabs

The low density storm snow is being pushed and forming soft storm slabs. These are mostly limited to ridgeline, however they have been found in isolated open slopes at the upper limit of TL.

Avoid freshly wind loaded features.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Soft slabs are present in lee and cross-loaded features in the ALP and the upper reaches of TL. The hard slab created in January is the foundation for these new slabs. The smooth character of that hard slab is making this a poor bonding layer.

Avoid cross loaded slopes at or above treeline.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Feb 24th, 2013 2:00PM