Avalanche Forecast

Issued: Jan 28th, 2012 4:23PM

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

lisa paulson, Parks Canada

Banff Yoho Kootenay.

Updated forecast is still calling for up to 30 cm overnight and another 15 tomorrow. Coupled with strong W winds & freezing levels rising to 1600 m, expect hazard to rise, and may tip into EXTREME in areas receiving the forecasted amounts or more.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Intensity of incoming weather systems is uncertain

Problems

Wind Slabs

Recent control in Yoho & field obs in Kootenay today confirm the Jan 20 facet interface still active. 60-80 cm now sits over this layer. With additional load expect avalanches on this layer that may step to ground in thin snowpack areas.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Storm Slabs

Up to 20 cm has fallen along the divide today. Expect an additional 30 overnight, and another 15 tomorrow. Strong west winds will accompany the snow fall. If this forecast is correct, natural and skier triggered avalanches are certain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

This layer is of concern in thinner snowpack areas. In Kootenay, a skier triggered a 60 cm thick size 1.5 slab, propagated 50 m on a 45 deg, open wind affected slope. Skier was carried 150 m and lost their pole - thx for the report!

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Jan 29th, 2012 4:00PM