New flurries and wind will contribute to ongoing slab development. The most reactive deposits will be around ridgetop and in wind-loaded terrain.
New snow and flurries will be impacted by winds, building slabs and adding to older, harder wind slabs. Expect to find more reactive deposits in areas with deeper deposits of fresh snow.
FRIDAY NIGHT: Cloudy with isolated flurries, 5-10 cm. Alpine high temperature -5 C. West wind 15-35 km/hr.
SATURDAY: Flurries, 5-15 cm with the heaviest snowfall amounts expected around Kootenay Pass. Alpine low temperature -9 C. West-southwest wind 20 gusting to 50 km/hr.
SUNDAY: Continued flurries, 5-10 cm. Alpine low temperature -10 C. West-northwest wind 25 gusting to 55 km/hr.
MONDAY: Mix of sun and cloud. Alpine low temperature -11 C. Northwest wind 15-40 km/hr.
Explosive work Wednesday produced size 1.5-2 wind slab and cornice avalanches. Several small (size 1) natural and skier-triggered wind slab avalanches have been reported on east/northeast aspects in the alpine over the past few days. At least one of these occurred near treeline and was reported to have slid on a crust buried around 20 cm below the surface.
New snow and wind will further wind slab development in lee features at alpine and upper treeline elevations. The new snow is failing of a variety of surfaces: hard windslabs around ridgetops and northerly alpine features, soft slabs and 10-15 cm lower density snow in sheltered terrain, a thin sun crust on solar aspects, and scoured features in exposed terrain.
A thick rain crust to mountain top sits below 25-45 cm of recent storm snow in the east of the region and 40-100 cm in the west. Recent avalanches slid on the crust or released within the storm snow. However, recent information indicates the bond at the crust is improving. Weak facet/crust layers near the base of the snowpack have not been an active avalanche problem recently.
