Avalanche Forecast

Issued: Mar 29th, 2017 5:12PM

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

snow safety, Parks Canada

Banff Yoho Kootenay.

Pay attention to day time heating. Several solar released avalanches were observed out of steep terrain on Wednesday.

Summary

Weather Forecast

Thursday will bring a mix of sun and cloud and some convective flurries. Winds will be generally light from the west and freezing levels will rise to 2100 m. A clearing trend with similar temperatures is forecast for Friday.

Snowpack Summary

10-15 cm of recent storm snow sits over a well settled100cm+ slab which sits precariously over weak basal facets at treeline and above. Tests show easy to moderate sudden collapse results in the facets. The surface snow is of a mix of soft snow in the shade, melt-freeze snow below treeline, and sun crust on sun exposed slopes.

Avalanche Summary

On Tuesday a size 3 avalanche was reported on the 'Onion Skin' near Bow Hut. A cornice dropped onto a slope which triggered the slide. It was reported that it ran for 800m.

Confidence

Problems

Deep Persistent Slabs

The snowpack throughout the region has a weak base and remains suspect. Approach all avalanche terrain with suspicion and exercise conservative route choices. The natural avalanche cycle has ended but human triggered avalanches are still possible.

Be wary of slopes that did not previously avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Wind Slabs

Fresh wind slabs have been reported on lee aspects in the alpine.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Cornices

There has been an increasing frequency of cornice failures this past week. Be wary of this as we transition into spring (cornice season).

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 30th, 2017 4:00PM