Avalanche Forecast

Issued: Nov 16th, 2013 4:17PM

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

conrad janzen, Parks Canada

Banff Yoho Kootenay.

It is early season and many places do not have enough snow for good skiing. Snow is accumulating in gullies and lee features. Skiers and ice climbers should be aware of increased wind loading going on over the next two days. CJ

Summary

Weather Forecast

An additional 10-15cm is expected on Sunday with strong W winds in the alpine and cool temperatures. Monday and Tuesday remain cool with a few flurries and a mix of sun and cloud.

Snowpack Summary

20-40cm of storm slab sits over the previous surfaces at tree line and above. Previous moderate to strong W winds created soft and hard slabs on N and E aspects. Above 2400m the Oct 27 melt freeze crust exists near the base of the snowpack and continues to provide a good sliding layer. The base of the snowpack consists largely of facets.

Avalanche Summary

Several slabs have been observed in alpine areas over the past 36 hours up to size 2. At higher elevations these are running on either the Oct 27 melt freeze crust or at the storm snow interface. Cornices are growing and fragile and several natural and human triggered failures have been observed recently.

Confidence

Due to the number of field observations

Problems

Wind Slabs

With increasing winds and new snow you can expect sluffing and new wind slabs to start forming by Sunday afternoon. The previous wind slabs from Friday remain a concern and are still susceptible to human triggering.

Be careful with wind loaded pockets. Be aware of wide variation in snowpack depthUse caution in lee areas in the alpine. Recent wind loading have created wind slabs.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Storm Slabs

In alpine areas the recent storm snow has begun to settle into a slab and sits over facets or the October 27 melt freeze crust. Several recent failures have been observed. Use caution in steeper terrain as the snowpack in general is quite weak.

The new snow will requires several days to settle and stabilize.Assess start zones carefully and use safe travel techniques.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Nov 17th, 2013 4:00PM