Avalanche Forecast
Issued: Feb 22nd, 2013 8:27AM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Good
Weather Forecast
Synopsis: There is a brief break between weather systems on Saturday before the next frontal system arrives late Sunday and into Monday. Saturday: Cloudy with light snow in the morning and gradual clearing through the day. The freezing level is near valley bottom and winds ease to moderate from the west-northwest. Sunday: Moderate snow â around 10 cm. The freezing level is near valley bottom and winds are moderate from the west. Monday: Snow easing in the morning with gradual clearing throughout the day. The freezing level remains near valley bottom.Â
Avalanche Summary
Avalanche activity on Thursday was primarily limited to loose dry avalanches in steep terrain, indicating that a slab had not yet formed. This has almost certainly changed today. Heavy snow and strong winds on Friday will likely result in a natural avalanche cycle which should continue into the weekend.
Snowpack Summary
By late Friday morning there was already up to 30 cm of new snow on the ground. This new snow was accompanied by strong west-southwest winds forming weak wind slabs in exposed lee terrain. The February 12 persistent weak layer (crust, and/or surface hoar) is now down 60-80 cm and is primed for triggering. Recent snowpack tests have shown easy to moderate "pops" results on this interface. Deeper persistent weak layers from early February and late January continue to show planar failures when moderate to hard forces are applied in snow pack tests. These deeper layers have not been reactive to the weight of a rider, but they may be triggered by large loads like an avalanche in motion (step-down avalanche), or a cornice fall.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 23rd, 2013 2:00PM