Avalanche Forecast

Issued: Jan 25th, 2016 4:10PM

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

grant statham, Parks Canada

Banff Yoho Kootenay.

Conditions are tricky right now! Avalanche control results today showed widespread explosive triggered avalanches between size 2 and 3 - some fracture lines propagated over 350 meters. Human triggering is likely, so manage your exposure carefully.

Summary

Weather Forecast

The region is currently under the influence of a NW flow, with the main storm track to our north. Starting Tuesday afternoon a system moves into the area and we can expect 5-10 cm through the afternoon and evening with temperatures around -5 and winds from the west, 25-50 km/hr.

Snowpack Summary

25-50 cm reactive slabs overlie the January 6 weak layer, and these slabs are reactive to explosive and human triggers. Their depth varies across the region, with Kootenay Park being the touchiest situation. The middle of the snowpack is facetted, which has been increasing the size of avalanches as they gain mass while descending.

Avalanche Summary

Monday's avalanche control work on highway 93 south resulted in widespread avalanches between size 2 and 3 with fracture lines ranging from 25-50 cm deep. In Kootenay Park, some fracture lines extended up to 350m wide and ran over 1500m.

Confidence

Problems

Wind Slabs

Windslabs are likely to be triggered in leeward areas above treeline - we are on the tail end of an avalanche cycle, and human triggering is likely in many areas.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Storm Slabs

This problem exists in deeper snowpack areas - such as Kootenay Park where slabs have been formed by settled snow overlying the Jan 6 surface hoar layer. Watch out - these are touchy and propagate easily.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 26th, 2016 4:00PM