Kootenay Boundary

Strong winds have redistributed loose snow and formed wind slabs. Lingering reactive wind slabs are most likely in wind-loaded areas: below ridgelines, under cornices, and around steep, unsupported features.

Moderate - Forecast snowfall amounts are uncertain on Tuesday

SUNDAY NIGHT: Cloudy with clear periods and isolated flurries in evening, trace accumulation. Alpine temperatures near -18C. Ridgetop winds light from the southeast.MONDAY: Mix of sun and cloud, isolated flurries in evening, trace accumulation. Alpine temperatures near -15C. Ridgetop winds light from the south-southeast.TUESDAY: Cloudy with flurries, 10-20 cm accumulation. Alpine temperatures near -8C. Ridgetop winds moderate from the south.WEDNESDAY: Flurries, 10-15 cm accumulation. Alpine temperatures near -8C. Ridgetop winds moderate from the east-southeast.

Several large (size 1-2.5) natural wind slab avalanches occurred on all aspects at treeline and above sometime late Friday evening. Widespread wind effect was noted through Friday with scouring and wind-loading on a variety of aspects. Small wind slabs (size 1-1.5) were reactive to skier traffic. On Wednesday, a skier remotely triggered a size 1.5 slab avalanche approximately 200 m away from them off the same ridgeline that they were traveling on, the suspect failure plain being the February 1st surface hoar interface that was buried last weekend. Additionally, slab avalanches failing on this layer were also easily triggered up to size 1.5 on north and and east-southeast aspects around 2000 m early in the week. With the cold temperatures and a bit of new snow, loose dry sluffing from steeper terrain features can be expected.

The recent wind event has create a variety of wind affected surfaces: scoured and wind-press in exposed terrain, hard wind slabs in wind-loaded areas and around the alpine, softer wind slabs and loose faceted snow in sheltered terrain and at lower elevations. This wind-affected snow covers on variety of snow surfaces, including buried wind crust on westerly aspects, sun crust on southerly aspects to mountain top, variable wind-affect in northerly terrain, and weak feathery surface hoar crystals in sheltered areas at treeline and below. The snowpack now hosts two buried surface hoar layers. The one that was buried on February 1st (down 20-40 cm) seems to be more predominant and reactive to human triggers than the one buried deeper down (40-80 cm). This deeper layer of surface hoar may be most reactive below treeline on shady aspects but doesn't seem to be a widespread problem in the region. The mid-pack is generally well-settled and strong.