Avalanche Forecast

Issued: Mar 31st, 2012 10:56AM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Cornices, Wind Slabs and Loose Wet.

jlammers, Avalanche Canada

Northwest Inland.

Summary

Confidence

Fair - Intensity of incoming weather is uncertain on Monday

Weather Forecast

Sunday: a mix of sun and cloud with light snowfall - light and variable winds - freezing level at 900m Monday: light snowfall - strong south winds - freezing level at 1000m Tuesday: light snowfall - moderate south winds - freezing level at 900m

Avalanche Summary

No reports of new avalanches from this region.

Snowpack Summary

Light amounts of new snow overlie wind slabs that may be found in unusual places, lower on the slope or in open areas below treeline. Windward aspects may become wind pressed, and even scoured. North aspects at higher elevations hold dryer, low density snow in the upper 20 cm. Spring-like conditions exist and crusts have formed on solar aspects at all elevations, becoming moist under sunny skies. Melt-freeze conditions exist @ treeline on all aspects. Below treeline has remained moist, with no recovery below 1500 m. The mid-pack is well consolidated. The mid February persistent weak layer, comprised of spotty surface hoar, facets and crusts, is buried 80-120 cm below the surface. No recent activity has been reported on this interface. It most likely needs a large trigger on a specific spot. If an avalanche occurs on this weak interface it will be very large and destructive. Below this the snowpack is well settled and strong. Cornices in the area are reported to be very large. Cornice failure could trigger an avalanche on the slope below.

Problems

Cornices

Large cornices exist in alpine terrain. A failure could be destructive by itself, and could also trigger an avalanche on the slope below. Use extra caution if the sun shines through.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 5

Wind Slabs

Strong south winds have built wind slabs in unusual places. Most likely found in upper elevations on lee slopes, and behind terrain features.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Loose Wet

With warmer spring temperatures, watch for loose wet snow avalanches in steeper terrain, especially when the sun is shining.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 5

Valid until: Apr 1st, 2012 9:00AM