Avalanche Forecast

Issued: Feb 15th, 2012 10:10AM

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

Avalanche Canada jlammers, Avalanche Canada

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

Moderate snowfall should start late Wednesday evening and continue until Thursday afternoon. Snowfall amounts are expected to be 15-20cm. Trace amounts are expected on Friday and mostly clear skies are forecast for Saturday. Winds should be moderate to strong from the southwest on Thursday and Friday, switching to light and northerly by Saturday. Freezing levels should be at about 700m for Thursday, 800m for Friday and 500m for Saturday.

Avalanche Summary

No new avalanches to report.

Snowpack Summary

A strong melt freeze crust exists below 1000m on all aspects. On shaded alpine features the surface is mostly wind pressed powder. Variable winds have redistributed 5-10cm of new snow into isolated pockets of wind slab on a variety of aspects in the alpine, although the reactivity of these windslabs has been most recently described as stubborn. The aforementioned new snow may overly buried a surface hoar layer (crystal size reported to be 1-4 mm) at treeline and below. This surface hoar layer seems most prevalent in protected inland areas. Deeper within the snowpack, a facet layer buried around Jan 20th is the greatest concern although triggering seems unlikely. This layer lies approximately 110-140 cm below the surface and still exhibits hard, sudden planar results in isolated snowpack tests.

Problems

Wind Slabs

An icon showing Wind Slabs
Forecast snow and wind will have set up sensitive new wind slabs at treeline and in the alpine.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Feb 16th, 2012 9:00AM