Regions
Kootenay Boundary.
Weather Forecast
Synopsis: The pattern over the next five days starts out cool, convective and gusty. It will gradually turn milder, more stable and less windy towards SaturdayFriday: Freezing Level: 1000m Precip: 2/5mm – 4/10cm Wind: Light gusting mod NorthSaturday: Freezing Level: 1100m Precip: No significant precip expected. Wind: Light gusting mod NorthSunday: Freezing Level: 1000m Precip: : No significant precip expected. Wind: Light, NE
Avalanche Summary
The storm snow sluffed easily on the previous snow surface that is a thin crust. Reports of skier triggered, fast moving, loose snow avalanches to size 1.5 came in from across the region. Over the past few days numerous size 1-2 avalanches have been triggered naturally, by skiers, explosives and vehicles. In most cases, the new snow was failing on the hard crust below. Many were soft slabs where the wind had sifted the snow onto lee slopes, and several were loose dry avalanches.
Snowpack Summary
The boundary pulled a respectable 20 - 30 cm of snow from Wednesday's storm. Much of this snow came to rest on a thin crust that is present on almost all aspects with the exception being due North. A thick supportive crust can be found down 50 - 80 cm. A buried surface hoar down 80 - 90 cm continues to fail in a sudden planar fashion when tested. Potentially large fragile cornices loom over many slopes.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.