Regions
Kootenay Boundary.
Wind slabs from the recent snowfall are expected to remain reactive to human-triggering. Field observations have been limited to date, so please share your observations on the Mountain Information Network (MIN) if you've been out in the mountains.
Confidence
Low - Due to the number of field observations
Weather Forecast
TUESDAY: Mix of sun and cloud, light north winds, alpine temperatures at -15.WEDNESDAY: Sunny, light winds, alpine temperatures at -16.THURSDAY: Isolated flurries, moderate southwest winds, alpine temperatures at -12.
Avalanche Summary
Although reports are limited, natural avalanche activity was reported in alpine terrain on Sunday and Monday, including loose dry avalanches and storm slabs up to size 2. Lingering wind slabs from the storm snow will likely remain reactive to human triggering at higher elevations in the upcoming days.
Snowpack Summary
25 cm of low density snow from the weekend is settling and will be thickest and most reactive on leeward features in wind exposed terrain. In some areas, the storm snow may sit above either a thin drizzle crust or small surface hoar layer, possibly making it more reactive. Surface hoar or surface facets will likely develop in the upcoming days, possibly creating a weak interface when the next storm arrives. A thick melt-freeze crust from mid-November is buried 40-80 cm deep. Facets have recently been reported above this crust, suggesting it may be possible to trigger this layer in shallow alpine start zones. The lower snowpack is generally strong and well-settled. Snowpack depths are 130-160 cm at treeline elevations.
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.