Avalanche Forecast

Moderate - Intensity of incoming weather systems is uncertain

SUNDAY NIGHT -Flurries, up to 5 cm / south to southwest winds, 25-50 km/h / alpine low temperature near -4MONDAY - Cloudy with flurries, 5-10 cm / southwest winds, 25-50 km/h, gusting to 60 km/h / freezing level 1600 m / alpine high temperature near -5TUESDAY - Snow, 10-20 cm / southwest winds, 20-50 km/h, gusting to 60 km/h / freezing level 1500 m / alpine high temperature near -4, low temperature near -6WEDNESDAY - Mainly cloudy with flurries, up to 10 cm / west to southwest winds, 20-40 km/h, gusting to 60 km/h / freezing level 1500 m / alpine high temperature near -5, low temperature near -8

Avalanche activity has been extensive in the Purcells over the past 5 days with daily reports of natural and explosive triggered avalanches to size 3.5, and human triggered avalanches to size 2.5. Many of these have been remote triggered (triggered from a distance).One very notable report on Saturday was a size 2.5 human triggered avalanche that was remotely triggered from 50-100 m away on a northwest aspect at 2250 m. A report of this avalanche can be found on the Mountain Information Network. (here)A natural avalanche cycle to size 4 was also reported in the region on Friday.

60-120 cm of snow sits on a weak layer of facets (sugary snow), surface hoar (feathery crystals), and a sun crust (on south facing slopes). Strong winds have promoted widespread slab formation.Another layer of surface hoar and sun crust is now buried 80-150 cm. The potential may exist for smaller avalanches to step down to this deeper layer, resulting in very large avalanches. The most likely areas for this layer to be a problem is where the surface hoar sits on the sun crust, which is most likely on steep south facing terrain at treeline.At the base of the snowpack is a crust that formed in late October. This layer is likely only a problem on large, steep 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.