Avalanche Forecast

Issued: Jan 17th, 2017 6:09PM

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.

Pay attention to the temperatures on Wednesday. The warming trend we are experiencing will increase the avalanche hazard. The Banff area in particular is experiencing very warm temperatures.

Summary

Weather Forecast

Wednesday will be mostly cloudy with some light snowfall expected. Up to 10 cm of new snow can be expected along the divide. Freezing levels will be around 1600 m in the Lake Louise area and 1700 m in the Banff area. A slight cooling trend is forecast for Thursday.

Snowpack Summary

In general the snowpack in this area is weak and facetted. Along the divide where the snowpack may be deeper a stronger midpack can be found. Moderate to strong SW winds over the last couple of days have created scouring, wind effect and hard and soft wind slabs in the alpine.

Avalanche Summary

A Class 2.5 avalanche was observed running over Rogan's Gully ice climb on Cascade on Tuesday. This was associated with above freezing temperatures in the Banff area today. Several skier triggered avalanches have been reported over last few days. These have released on the weak facet layer in the midpack.

Confidence

Problems

Deep Persistent Slabs

The midpack in most areas is weak and facetted. Any slab sitting overtop of this weakness should be considered suspect. While these slabs may be difficult to trigger, the result could be a large avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

Moderate to strong south and sw winds have scoured the alpine and created some new windslabs in alpine and some treeline features.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 18th, 2017 4:00PM