Kootenay Boundary

Triggering slab avalanches remains possible at all elevations and aspects. Carefully watch for signs of instability such as whumpfs and cracking.

Moderate - Wind effect is extremely variable

SUNDAY NIGHT: Clearing skies overnight, moderate northwest wind, alpine temperatures drop to -18 C.MONDAY: Mix of sun and cloud, moderate northwest wind, alpine high temperatures around -13 C.TUESDAY: Cloudy with isolated flurries and trace accumulations, moderate to strong northwest wind, alpine high temperatures around -13 C.WEDNESDAY: Cloudy with isolated flurries, light northeast wind, alpine high temperatures around -10 C.

Numerous skier triggered slab avalanches have been reported daily since Tuesday. Although most avalanches have been small (size 1-1.5), they have shown impressive propagation. See these examples from recent MIN reports here and here. Preliminary reports from Sunday indicate freshly wind loaded features were reactive to skier triggering, with a few size 1.5 avalanches reported on a variety of aspects. A persistent slab avalanche was remotely triggered slab on a east aspect at 1850 m. It failed on a 30 cm deep surface hoar layer. On Saturday, a few small (size 1-1.5) slab avalanches were triggered by skiers on convex terrain, especially on south aspects. On Thursday, strong wind formed fresh wind slabs that produced several size 1-2 natural avalanches. The wind slabs were also very reactive to human triggering and produced two large (size 2) skier-triggered slab avalanches (with  80 cm thick crowns).

Surface snow consists of a mix of low density snow and hard wind affected surfaces. 20 to 40 cm of snow from the past few days is gradually settling, and in some areas has shown signs of becoming reactive above above a surface hoar and crust layer that was buried on February 7th. This layer is suspect at all elevations, particularly on wind loaded slopes and on steep south-facing terrain.Two other surface hoar layers are buried 50 to 80 cm deep the snowpack (referred to as the February 1st and mid-January layers). Although they have not been reactive recently, they are still being monitored by professionals. These layers are most prevalent below treeline on shady aspects. The lower snowpack is well settled.