Avalanche Forecast

Moderate - Timing of incoming weather systems is uncertain.

WEDNESDAY NIGHT: Cloudy with flurries, accumulating up to 10 cm overnight. Moderate south wind. Freezing level valley bottom. THURSDAY: Snow increasing through the day, accumulating 20-30 cm. Moderate south wind with strong gusts. Freezing level rising to 1400 m. FRIDAY: Cloudy with isolated flurries, accumulating up to 5 cm. Light to moderate west wind. Freezing dropping to valley bottom. SATURDAY: Mix of sun and cloud. Light south wind. Freezing level valley bottom.

Since last Friday, there have been numerous natural and human triggered avalanches to size 2.5, and explosives triggered avalanches to size 3. Many avalanches reported were remote triggered (from a distance) As of Tuesday, numerous very large (size 2.5-3) natural avalanches continued to be reported. A notable human triggered size 2.5 avalanche occurred in Allan Creek on Saturday. The avalanche was triggered on a northeast facing alpine slope. A report of this avalanche can be found on the Mountain Information Network here. A size 4 natural avalanche was reported to have run full path, burying a road on the west side of Kinbasket Lake. This avalanche occurred in the North Columbia region, but it is a significant event and is very close to the boundary between the North Columbia and Cariboo regions. These full path avalanches can catch people by surprise, especially when there is little to no snow in the valley bottoms. A report of this avalanche can be found on the MIN here.

Recent storms have deposited 80-120 cm of new snow. This new snow sits on a weak layer of facets (sugary snow), surface hoar (feathery crystals), and a sun crust (on south aspects). Strong winds have promoted widespread slab formation, particularly with the most recent new snow available for transport. A weak layer from mid November is now buried up to 150 cm and consists of surface hoar in shady locations, and a sun crust on steep south facing slopes. The potential may exist for smaller avalanches to step down and trigger this deeper layer, resulting in very large avalanches. The most likely place for this layer to be a problem is on steep, south facing slopes at treeline where the surface hoar sits on the sun crust. At the base of the snowpack is a crust that formed in late October. The probability of triggering this layer is low, but the most suspect areas would be large, steep, rocky alpine features with a shallow snowpack. It would likely take a large trigger such as a cornice fall to produce an avalanche on this layer.