Regions
Kootenay Boundary.
Avoid south slopes. They have been wind loaded and will become weak with the intense warming and sun.
Confidence
High - The weather pattern is stable
Weather Forecast
THURSDAY: Alpine sun with some valley clouds, light northwest wind, freezing level around 3300 m with inversions in the valleys.FRIDAY: Alpine sun with some valley clouds, light northwest wind, freezing level around 3000 m with inversions in the valleys.SATURDAY: Increasing cloud, moderate west wind, freezing level around 2700 m with inversions in the valleys.
Avalanche Summary
On Tuesday, a small (size 1) natural storm slab avalanche was reported on a southeast slope at 2150 m. Previous activity from the weekend included some larger natural and skier triggered storm slabs up to size 2, with the largest cause by recent loading from northwest winds.
Snowpack Summary
Dramatic warming will cause widespread melting of the surface snow, especially on south-facing slopes. Crusts may form overnight, but will melt quickly in the mornings. 30 - 50 cm of new snow has fallen in the past week. At higher elevations, northwest winds redistributed the snow, forming wind slabs on downwind (lee) features. Below the recent storm snow you'll likely find a couple of widespread crusts (2 to 5 cm thick) which formed as a result of late November's rain. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 100-170 cm in the alpine, 50-100 cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks.
Problems
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
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.