Avalanche Forecast

Issued: Mar 29th, 2014 4:00PM

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

stephen holeczi, Parks Canada

Banff Yoho Kootenay.

Excellent skiing conditions. We are more concerned with the Feb.10th/basal layers in thin snowpack areas (mainly E of the divide) than the deeper snowpack regions (mainly W of the divide.)

Summary

Weather Forecast

15cm is expected in the Bow Summit area, 10 in Lake Louise and Sunshine areas on Sunday. Winds will be light gusting moderate and temperatures will be cool in the alpine and will go above freezing in the valley bottoms. On Mon and Tues, clearing skies and light winds may raise the hazard on solar aspects in the afternoon.

Snowpack Summary

Up to 47cm HST, generally bonding well with more wind effect today in alpine areas. In shallow, weaker snowpack areas, the basal facets and Feb10 layers are still reactive in field tests. In deeper, uniform areas these problems are less of a concern. On S aspects there are a few buried suncrusts. Moist snow below 1600m today in Yoho on all aspects.

Avalanche Summary

On a flight E of the Lake Louise ski area today, numerous avalanches were observed in alpine areas mainly on E and SE aspects within the last 24-36 hours. These appeared to be either in the recent HST or on a deeper layer, likely the Feb.10th. A skier accidental sz 1-1.5 was also reported in the Lipalians today which went to ground (80cm).

Confidence

Freezing levels are uncertain on Monday

Problems

Persistent Slabs

In areas with uneven, shallower or weaker snowpacks, we remain concerned with the Feb 10th midpack layer of crust/facets/surface hoar, and the basal layer. Choose conservative, well supported terrain in these areas.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be wary of slopes that did not previously avalanche

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

These are mainly confined to the immediate lees of ridges. Monitor slab development with wind gusts tomorrow as this may develop into more of a problem.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 30th, 2014 4:00PM