Avalanche Forecast
Issued: Nov 24th, 2012 8:25AM
The alpine rating is Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Due to limited field observations
Weather Forecast
Synopsis: The weather pattern is changing as a ridge of high pressure builds in from the southwest resulting in drier conditions and slightly cooler temperatures for the next few days. Sunday: A mix of sun and cloud. The freezing level is around 800-1000m. Winds are generally light. Monday: A mix of sun and cloud. The freezing level is around 1000m. Tuesday: Most likely another dry day, but we should see a frontal system arrive Tuesday night or Wednesday morning.
Avalanche Summary
Avalanche control on Whistler Mountain on Saturday produced one Size 2 avalanche on a northeast aspect that appeared to release on the early November facet/crust weakness. The arrival of cooler and drier weather will reduce the likelihood of natural avalanches, but human triggered avalanches are still possible.
Snowpack Summary
New wind slabs have likely formed in exposed northwest to northeast aspects at treeline and in the alpine. The main snowpack feature worth noting is a rain crust buried in early November and now down around 80cm at treeline as as deep as 1.5m in alpine areas. A weak layer of facets on top of and within this crust is worth remaining suspicious about (sudden collapse fracture character with propagation potential with snowprofile/ snowpack tests). Widespread whumpfing and cracking on this layer has also been reported from the Whistler area. Because this weakness is so close to the ground in most areas, associated avalanche activity will likely be limited to slopes with smooth ground cover (e.g. scree slopes, rock slabs, summer firn, glaciers, etc.). The total snowpack depth at treeline is around a metre. Alpine areas are deeper but more variable. Most slopes below treeline are still below threshold depths for avalanches. For more information check out the telemarktips.com forum , the Mountain Conditions Report, and Wayne Flann's Avalanche Blog.
Problems
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 25th, 2012 2:00PM