Avalanche Forecast

Issued: Nov 23rd, 2013 4:00PM

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

Stephen Holeczi, Parks Canada

Banff Yoho Kootenay.

Ski quality is still not great throughout the forecast region, and below treeline travel is mainly faceted. Most ice climbs are in decent early season shape. SH

Summary

Weather Forecast

W-NW alpine winds Sunday moderate gusting strong. Alpine temperatures should stay below freezing with a mix of sun and cloud and no precipitation.

Snowpack Summary

The Oct. crust/facet layer at the base of the snowpack is the primary concern in the forecast region. Wind slabs up to 1 meter thick over this layer have been stiffening up due to constant W winds. The crust is most prevalent on polar aspects in the alpine, and mainly a facet layer on solar aspects. Below treeline is faceted powder over the ground.

Avalanche Summary

Lake Louise reported more activity than there has been over the last few days, and explosive control was producing size 2`s over the crust on steep NE/N alpine terrain. They attribute this to the stiffening wind slabs over the crust. Sunshine reported one size 2.5 on an E asp. seen outside the boundary, likely occurring within the last 24 hours.

Confidence

Due to the quality of field observations on Saturday

Problems

Wind Slabs

Harder wind slabs on steep, lee slopes are prone for triggering larger avalanches on the Oct. crust or facets. Steep side walls and exposed ledges on alpine ice climbs are other areas to be cautious of wind slabs.

Avoid freshly wind loaded features.Be aware of the potential for wide propagations due to the presence of hard windslabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Nov 24th, 2013 4:00PM