Avalanche Forecast
Issued: Dec 17th, 2012 8:00AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
danyelle magnan,
Parks Canada
A few hours of gusty southerly winds quickly formed thin windslabs above treeline yesterday.
Summary
Weather Forecast
Expect up to 5cm of snow, mostly cloudy skies and moderate S'ly winds today. A brief ridge of high pressure will bring cool and dry conditions on Tuesday with sunny periods, alpine temps dropping to -20 and N'ly winds. On Wednesday, the next system will move in with increasing cloud, strong SW winds and 10cm by the end of the day.
Snowpack Summary
At treeline and above, thin soft windslabs have formed on wind exposed features. Elsewhere, 40cm of loose storm snow overlies a well settled snowpack. The Nov28 surface hoar down 80cm and is found in some locations. The early Nov crust is widespread and down 1.5m. Tests on these layers indicate they would be hard to trigger.
Avalanche Summary
No new natural avalanches were observed yesterday. Avalanche technicians traveling over Little Sifton and into the Hermit Meadows area found 10cm thick windslabs on convex features that were easily triggerable to size 1 above 2300m.
Confidence
Intensity of incoming weather systems is uncertain
Problems
Wind Slabs
Yesterday, avalanche technicians found thin, touchy windslabs above 2300m that were easily triggerable on convex, unsupported features. They are of most concern where even a small avalanche would have high consequences; steep, complex terrain.
Assess start zones carefully and use safe travel techniques.Be cautious as you transition into wind affected terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 18th, 2012 8:00AM
