Avalanche Forecast

Issued: Dec 12th, 2013 4:47PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

5-15 cm has fallen in the last few days and has created touchy wind slabs on NE features. LP

Summary

Weather Forecast

Continued light flurries, warm alpine temperatures (-6C), and light to moderate west winds with strong gusts expected for the next 2 days.Â We may see more intensive flurries on Sunday adding to the existing storm and wind slabs and in turn increase the avalanche hazard.

Snowpack Summary

There is 50-70 cm of snow at tree line which is generally weak, and facetted, but there is some mid-pack support. Some fresh wind and storm slabs exist in lee alpine terrain which may be reactive to skier triggering. The October crust is 10-20 cm from ground and producing mod-hard results with comp. test.

Avalanche Summary

No new natural avalanche activity observed in the last several days. Sunshine forecasters reported ski cutting a size 1.5 avalanche in previously worked terrain. It was a 10-15 cm thick storm slab over a wind slab, which stepped down to the basal rain crust or facets. It was on a lee NE facing alpine feature.

Confidence

Track of incoming weather systems is uncertain

Problems

Wind Slabs

This layer is a concern in isolated areas loaded by wind. These slabs sit on a weak facetted base. There has been no recent natural avalanches on this layer, but it still may be triggered by skiers or climbers.

Be careful with wind loaded pockets while approaching and climbing ice routes.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Storm Slabs

Thin (10-15 cm thick) touchy,low density, storm slabs have been reported in the region on lee features.

The new snow will require several days to settle and stabilize.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 13th, 2013 4:00PM