Avalanche Forecast
Issued: Jan 9th, 2013 9:02AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
Peter,
Avalanche Canada
Summary
Confidence
Fair - Due to limited field observations
Weather Forecast
Synopsis: A ridge of high pressure will build in for Thursday. The ridge is interrupted on Friday as a weak disturbance pushes through. Thursday: Mainly sunny. Light northwest winds. Freezing level at valley bottom.Friday: A chance of flurries or light snow. Light northwest winds. Freezing level at valley bottom.Saturday: A mix of sun and cloud. Freezing level remains at valley bottom.
Avalanche Summary
There is one new report of a skier controlled size 2 avalanche in the northern part of the region. The slide released on a steep convex roll below treeline and likely failed on the late December persistent weakness.
Snowpack Summary
50-100cm of storm snow has fallen in the past 10 days or so. Weaknesses exist within and under this recent storm snow including touchy surface hoar and/or facets from the end of December under it all. Recent strong southwesterly to easterly winds have set up wind slabs in many exposed lee areas. A deeper surface hoar layer was buried at the beginning of December and is now down well over a metre, but there are no recent reports of activity on this layer. Near the base of the snowpack, a crust/facet layer continues to concern local avalanche professionals. This weakness is unlikely to be triggered by a single person, but it remains possible with a very heavy load (e.g. cornice fall) or from a thin-spot trigger point.
Problems
Persistent Slabs
A weak layer of surface hoar and/or facetted snow exists under the recent storm snow and has been susceptible to human triggering.
Choose well supported terrain without convexities.>Whumpfing is direct evidence of a buried instability.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 10th, 2013 2:00PM
