Avalanche Forecast

Issued: Mar 6th, 2017 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Storm slabs are sensitive to human triggering and a natural avalanche cycle continues. Use caution on and around recently loaded slopes.

Summary

Confidence

Moderate -

Weather Forecast

Tuesday will be cloudy with sunny periods and isolated flurries. Alpine temperatures will reach a high of -15 C, with ridge-top winds out of the SW at 15-30 km/h. Wednesday could see a weak snow storm with accumulations near 5cm.

Avalanche Summary

Several natural and cornice triggered avalanches up to size 3.0 have occurred over the past 72hrs, in some cases running full path. Avalanche control on Mt. Rundle produced good results up to size 2.5. A public report on the Mountain Information Network (MIN) describes a cornice triggered size 3.0 avalanche in the Tryst Lake area with a very wide propagation. This slide may have also sympathetically triggered additional smaller avalanches.

Snowpack Summary

Recent storm snow totals now average 50cm at Treeline. Storm slabs have formed in lee and cross-loaded features in the Alpine and at Treeline and seem prime for human-triggering in many areas. Cornices are large and several failures have occurred in recent days. Extensive wind transport at ridge-crest.

Problems

Storm Slabs

Storm slabs between 40 and 65cm thick are found in lee and cross-loaded features at Treeline and above. Natural avalanche activity associated to this problem continues, and many slopes appear primed for human-triggering.

If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Persistent Slabs

An avalanche initiated in the upper snowpack could step down to a deeper weak layer.

Be aware of the potential for wide propagations.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Cornices

Several cornice failures have occurred in the past 3 days which have triggered deep and large avalanches.

Pay attention to overhead hazards like cornices which could easily trigger persistent slabs.Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.

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

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Valid until: Mar 7th, 2017 2:00PM