Regions
Kootenay Boundary.
With snow and wind in the forecast for Friday, watch for fresh windslabs building in alpine, lee areas throughout the day.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
FRIDAY: Cloudy, flurries. Accumulation 5-10 cm. Ridge wind light to moderate from the west. Temperature -5. Freezing level 800 m.SATURDAY: Mix of sun and cloud, light flurries. Accumulation trace. Ridge wind moderate from the northwest. Temperature -9. Freezing level 500 m.SUNDAY: Cloudy, flurries. Accumulation 5 cm. Ridge wind light to moderate from the southwest. Temperature -7. Freezing level 600 m.
Avalanche Summary
There have been no reports of avalanche activity since the weekend when small, loose, dry avalanches were observed from skier traffic in steep terrain on Saturday.
Snowpack Summary
The snow surface varies widely depending on aspect and elevation. On solar aspects a thin melt-freeze crust exists. On northerly aspects, feathery, surface hoar crystals (10-30 mm in length) have been observed below treeline as well as protected areas at treeline. In the alpine the surface consists of sugary snow (facets) and hard, wind scoured snow. Below the snow surface the upper snowpack is well settled and overlies a series of late-November crusts which is now buried 20-50 cm and is 15-25 cm thick. Recent snowpack tests have produced hard, resistant compression test results within the layers of this crust. Below the crust layer the lower snowpack is moist and well settled.
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.