Regions
Kootenay Boundary.
A Special Public Avalanche Warning is in effect for this region. The mountains are still primed for human-triggered avalanches, especially at higher elevations.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
FRIDAY NIGHT: 10-15 cm new snow, falling as rain below 1700 m. Strong southerly winds.SATURDAY: Mostly dry. Freezing level around 1000 m. Moderate southwesterly winds. SUNDAY: 5-10 cm new snow. Freezing level around 1500 m. Strong southerly winds.MONDAY: 10-15 cm new snow. Freezing level around 1500 m. Moderate southwesterly winds.
Avalanche Summary
Numerous natural and explosives triggered avalanches to size 2 were reported in the region on Wednesday. Expect the storm slab to remain reactive with high freezing levels and strong winds.
Snowpack Summary
Approximately 50 cm of recent storm snow has fallen in the region with strong southerly winds. This snow sits on top of a weak layer of facets (sugary crystals), surface hoar (feathery crystals) and a sun crust on south aspects. Recent "sudden" snowpack test results on this layer indicate it still has the potential to release avalanches.Lower in the snowpack there were a couple of previous weak layers in the middle of the snowpack that appear to have become inactive, and a layer of sugary facets near the base of the snowpack. This latter layer could possibly cause problems on cold (north facing) slopes at high elevations where the snowpack is thin, but in most places, this is unlikely.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
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.