Avalanche Forecast

Issued: Mar 22nd, 2016 9:28AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Cornices, Storm Slabs and Persistent Slabs.

pgoddard, Avalanche Canada

Kootenay Boundary.

Give cornices a wide berth.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

A frontal system is expected to bring around 10-15 cm snow on Wednesday night, with moderate to strong SW winds and the freezing level around 1400 m. Â Snow showers linger on Thursday before a ridge brings clearing skies on Friday.

Avalanche Summary

A few small storm slabs were triggered by explosives and a skier yesterday.

Snowpack Summary

Surface snow layers are becoming moist and weak in the heat of the day, but generally settling and bonding with warm temperatures and sunshine. Several crusts are buried in the upper snowpack. Some of these are breaking down on sunny aspects. The late February persistent weak layer down 70 to 120 cm remains a lingering concern. Test results are variable, with occasional sudden planar (pop) results. This interface may remain more reactive on northerly (shaded) aspects above about 1700 m, where buried surface hoar has the best chance of preservation. On sunny aspects, this interface may be a crust/ facet layer. It is most likely to be triggered by a cornice fall or from a thin snowpack area.

Problems

Cornices

Large cornices are threatening many slopes.

Do not travel on slopes that are exposed to cornices overhead.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Storm Slabs

A new storm slab may develop, especially on features in the lee of the wind.

Choose well supported terrain without convexities.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

While becoming unlikely, a persistent slab could still fail with a large trigger like a cornice fall, or from a thin snowpack area.

Be aware of the potential for large, deep avalanches due to the presence of buried weak layers.>Avoid thin areas that may propagate to deeper instabilities.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 23rd, 2016 2:00PM