Avalanche Forecast

Issued: Dec 7th, 2011 4:01PM

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

Brian Webster, Parks Canada

Banff Yoho Kootenay.

A temperature inversion is forecast for Thursday. Upper elevation temperatures may get close to zero degrees. Pay attention to alpine slopes that may be warming up.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Problems

Deep Persistent Slabs

The weak base of depth hoar and facets is now less sensitive to human triggering , however skier triggered and natural avalanches have recently been observed on this layer. A natural with a 400 m crown was observed on Mt Lefroy today.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 3

Wind Slabs

Strong winds have been moving snow from the west and north for the last few days and hard wind slabs have formed. It is likely that any slab will immediately step down to the weak base. Choose moderate slope angles & low consequence terrain