Avalanche Forecast

Fair - Forecast snowfall amounts are uncertain on Friday

Snowfall is expected to become more intense overnight and into Friday (up to 40cm by Friday afternoon). Winds are forecast to become moderate to strong from the SW to NW. Freezing level at valley bottom. Snowfall becomes light on Saturday before a second pulse of snow arrives late on Sunday.

Natural avalanches have been reported up to size 2 where the recent storm snow has been transported into a wind slab. Some of these avalanches have released on or stepped down to the mid-December persistent weak layer of surface hoar and crust.

Snow and wind forecast for Friday will add stress to a snowpack that varies across the region, but is volatile in some places. New snow is expected to hide wind slabs which formed recently in response to strong northerly winds. Storm slabs or wind slabs may overload the persistent weak layer of mid-December surface hoar. This layer is buried under a consolidated slab, anywhere from 15-80 cm deep. Below 2100 m, the buried surface hoar sits on a thick, solid crust and has been acting as a perfect sliding layer. In the worst affected areas, this layer sports well preserved 10-50 mm crystals, especially within a few hundred metres of treeline. A hard rain crust with facets from early November is buried more than a metre down and is currently unreactive. However, triggering from shallow rocky and unsupported terrain remains a concern.