Avalanche Forecast

Issued: Feb 23rd, 2017 4:50PM

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

brian webster, Parks Canada

Banff Yoho Kootenay.

The natural avalanche cycle has abated, but human triggered avalanches are still possible. Current conditions are difficult to predict and a wide margin of safety is required.

Summary

Weather Forecast

Friday will be mostly cloudy with only isolated flurries. Daytime highs of -12 in the alpine and the freezing levels will be near valley bottom. Winds will be mostly light.

Snowpack Summary

There is 20-30 cm of low density storm snow (with very little wind effect) at treeline. Common through the area are the weak facets in the lower half of the snowpack, particularly at lower elevations and east of the divide. Surface hoar was observed on the surface on Thursday and there is a thin rain-crust below the storm snow at lower elevations

Avalanche Summary

There was good visibility today and theÂ field team observed evidence of cycle from the past week including a number of skier triggered and natural avalanches around Lake Louise Ski Area and along the east side of the Banff Jasper Highway. No fresh avalanches reported in past 24 hours.

Confidence

Problems

Deep Persistent Slabs

There is a thick slab over a structurally weak snowpack in most areas. Likely areas of triggering are in thin parts of a slope or rocky outcrops at tree line and above. A failure can propagate to deeper areas and cause large avalanches.

Be aware of thin areas that may propogate to deeper instabilites.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Valid until: Feb 24th, 2017 4:00PM