Regions
Kootenay Boundary.
Forecast stormy weather is expected to keep avalanche danger elevated over the next few days.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Tuesday
Weather Forecast
Overnight: 3-5 cm of new snow above 1000 metres combined with light southwest winds. Tuesday: 3-5 cm of new snow with moderate southwest winds, and daytime freezing levels around 1600 metres. Wednesday: 5-10 cm of new snow combined with moderate southwest winds, and daytime freezing levels around 1600 metres. Thursday: Light winds with a chance of flurries in the morning and some clearing in the afternoon, daytime freezing levels near 2000 metres.
Avalanche Summary
Loose wet avalanches were reported from the Kootenay Pass area on Monday up to size 1.5 on all aspects from 1600 -2000 metres elevation.
Snowpack Summary
Stormy weather over the past week brought roughly 40-50 cm of snow to the region. Periodic high freezing levels and solar exposure over the same period formed a series of crusts (March 19-24) that exist within this upper snowpack at lower elevations and on solar aspects. The new snow and series of crusts lie over a more widespread (March 14) rain crust that exists at all elevations. Moist or wet snow exists below this rain crust. The late-February facet / surface hoar interface (90-140 cm deep), the mid-February crust (110-150 cm deep), and basal facets in shallow snowpack areas may still be present at upper elevations. Overlying crusts have been noted acting as a bridge over these layers and any remaining reactivity is likely limited to high alpine locations.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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 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.