Avalanche Forecast
Issued: Dec 29th, 2016 4:29PM
The alpine rating is Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Wind effect is extremely variable
Weather Forecast
FRIDAY: Dry, with some clear spells, but strong northwest winds blowing up to 60 km/h at ridgetop. Temperatures around -15C. SATURDAY: Light snow 3-5 cm with continued strong northwesterly winds 60-80 km/h at ridgetop. Temperatures around -9C. SUNDAY: Dry with clear spells. Continued strong winds from the north. Temperatures around -10C.
Avalanche Summary
No avalanches have been reported since Monday, when, a skier remote triggered a size 1.5 wind slab in the Hankin area on a north aspect at treeline (see MIN report). Wind slabs will remain touchy throughout the week, as sustained winds will redistribute the new low density snow. The additional load of new snow will also keep deeper persistent weak layers reactive, making it possible to trigger larger avalanches.
Snowpack Summary
Snowpack depths in this region are still shallow - around 1 m or so, meaning there are a lot of weak sugary facets in the snowpack at this time. Recent storm snow has been redistributed by the wind, and wind slabs are widespread behind exposed ridges. Where hard wind slabs overlie weak facets, the structure is ripe for human-triggered avalanches. In addition to the sugary facets, you may find a layer of feathery surface hoar (up to 15 mm in sheltered areas), buried around 15-25 cm below the surface. There is another weak layer that formed during the early December cold snap which is now about 40-60 cm deep. A crust from mid-November may be found close to the bottom of the snowpack nestled in amongst the facets. We don't have a lot of information about these layers, but it's worth noting the layer responsible for most of the large avalanches during the big storm just before Christmas was the mid-November rain crust.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 30th, 2016 2:00PM