Avalanche Forecast

Issued: Mar 8th, 2013 4:00PM

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

chris gooliaff, Parks Canada

Banff Yoho Kootenay.

Touchy slabs exist where the storm slab overlies a weak, sugary snowpack. Whumphing and shooting cracks are obvious signs of this condition.

Summary

Weather Forecast

Mainly sunny tomorrow with a high solar impact on southerly aspects. Winds will remain light from the NW, temp's will be rise to slightly above normal in the afternoon with the aid of the sun, and no precipitation is expected.

Snowpack Summary

The storm snow from last weekend continues to strengthen as a unit, with no obvious shears within it. It also seems to be bonding reasonably well to the underlying snow surfaces. However, in areas of thinner snowpack (east of the Divide) and on steeper, southern aspects, the storm slab remains touchy and human triggering to size 3 is possible.

Avalanche Summary

Wednesday, a group of skiers remotely triggered, from 100m away, a size 3 slab near Dolomite Peak. They reported it failed on a SE aspect and the crown was up to 2m thick. Today, a field team around the Sunshine area noted several whumph's and cracking in the snowpack near wind-effected features.

Confidence

The weather pattern is stable

Problems

Storm Slabs

The storm slab seems to be bonding to older surfaces. West of the Divide, the storm slab is stubborn and harder to move, however slabs are still touchy east of the Divide where they overlie a weak, shallow, faceted snowpack.

Avoid shallow snowpack areas where triggering is more likely.Choose the deepest and strongest snowpack areas on your run.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Loose Wet

Clear skies, calm winds, and a stronger, March sun will likely create unstable conditions on steep, southern aspects. This will be more of a problem at lower elevations.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Be very cautious with gully features.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 9th, 2013 4:00PM