Avalanche Forecast

Issued: Feb 18th, 2012 10:07AM

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

Avalanche Canada jlammers, Avalanche Canada

Summary

Confidence

Fair - Timing of incoming weather is uncertain on Sunday

Weather Forecast

Sunday: Light snowfall / moderate southwest winds increasing to strong in the evening / freezing level @ 500m Monday: light snowfall / moderate southwest winds / freezing level @ 700m Tuesday: moderate snowfall / strong southwest winds / freezing level @ 700m

Avalanche Summary

No new avalanches have been reported.

Snowpack Summary

About 15cm of snow that fell over the past week sits over a variety of old surfaces: melt-freeze crusts exist on all aspects at lower elevations as well as on south-facing slopes higher up, and well-settled powder is found on shaded aspects in the alpine. Weak surface hoar crystals (size 3-4mm) are sandwiched between the old surfaces and the newer snow. The distribution of the surface hoar seems to be up to treeline on all aspects and on sheltered features in the alpine. This upper snow pack structure will be the big thing to watch as the overlying slab develops. I expect to see gradually increasing reactivity in the surface hoar interface with incremental loading and higher winds forecast for this week. Check out our Forecaster's Blog for some thoughts on incremental loading. The mid and lower snowpack is generally well settled and strong.

Problems

Wind Slabs

An icon showing Wind Slabs
Increasing winds will redistribute surface snow into wind slabs on lee slopes.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Feb 19th, 2012 9:00AM