Avalanche Forecast

Issued: Feb 15th, 2014 4:00PM

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

stephen holeczi, Parks Canada

Banff Yoho Kootenay.

By definition the danger rating is considerable on Sunday, however, the backcountry should be approached with caution. More snow is on its way and may bump the hazard rating back to high with minimal input (snow/wind). AB

Summary

Weather Forecast

Another system is expected to enter the forecast region starting Sunday. It will deposit approximately 40cm of storm by Tuesday evening. Accompanying the precip is strong westerly wind. We will therefore see a rise in the danger rating after Sunday, likely back to high.

Snowpack Summary

The storm snow from late last week is starting to settle and currently amounts to approximately 60cm. Winds, warm temps causing slab development in exposed areas, which overlies a complex layer of facets, surface hoar and sun crust on solar aspects. Below this a generally well settled midpack overlying the basal depth hoar layer.

Avalanche Summary

Avalanche control today produced many avalanches, but they were smaller than expected. On the Sunshine Road and Vermillion Slide paths on 93S slab avalanches up to size 2 were controlled with explosives. All of these avalanches were sliding on the Jan 30th surface hoar/facets layers approx 40cm deep.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Monday

Problems

Persistent Slabs

This layer is still touchy. Avalanche control was producing results on this layer today on the Sunshine Road and 93S.

The new snow will require several days to settle and stabilize.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Based on current wind patterns from our remote weather stations, and available new snow for transport, wind-slabs will still be lurking in the alpine, approximately 20-60cm thick.

Avoid areas with overhead hazard.Avoid freshly wind loaded features.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 16th, 2014 4:00PM