Avalanche Forecast

Issued: Mar 26th, 2014 4:00PM

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

Grant Statham, Parks Canada

Banff Yoho Kootenay.

20-40 cm of light, dry snow has fallen since Wednesday - so far under light wind conditions. The wind will make or break the avalanche danger over the next 24-hours. If the wind picks up - the avalanche danger will rise. Ski conditions are excellent.

Summary

Weather Forecast

The current storm pattern is forecast to continue through to Saturday, with daily accumulations of 10-15cm expected. By mid-day Thursday we expect close to 40cm to have fallen over the higher terrain. Wind is forecast to be light in the valley bottoms, and moderate from the west at the ridge top elevations. Temperatures will stay cool (-5 to -13).

Snowpack Summary

20-40 cm of light, dry storm snow has fallen across the forecast area since Wed night. This new snow sluffs easily and runs far on the underlying surface and has been blown into small, but very touchy windslabs in alpine areas. Deeper in the snowpack the Feb 10 layer remains a real concern in shallow snowpack areas such as the Kootenay burns.

Avalanche Summary

One skier triggered size 1.5 avalanche near Sunshine in a steep, alpine chute. Minimal observations due to poor visibility.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Persistent Slabs

There are two layers of concern in the upper meter of the snowpack that continue to produce shears in isolated areas and have a high degree of uncertainty. Be very mindful of this problem in areas that have not previously avalanched.

Be wary of slopes that did not previously avalanche

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

40 cm of loose snow is available to be blown into soft slabs by the wind. So far this storm has brought light winds, but we expect small windslabs to develop at the highest elevations where there has been some wind.

Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Loose Dry

Loose dry sluffs are running easily and gaining mass as they progress down the slope. Generally only small slides are anticipated, but watch your exposure to cliffs and trees as these can easily knock you off your feet.

Be cautious of sluffing in steep terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely - Certain

Expected Size

1 - 2

Valid until: Mar 27th, 2014 4:00PM