Kootenay Boundary

The recent storm snow is expected to remain reactive to human triggering on Tuesday, especially in wind loaded terrain and on steep unsupported slopes. Conservative terrain selection is still recommended.

Moderate -

A mix of sun and cloud is expected on Wednesday with the possibility of lingering flurries. Alpine wind is forecast to be moderate from the west and treeline temperatures are expected to be around -10C. Similar conditions are expected for Thursday and Friday with a mix of sun and cloud, light alpine wind, and treeline temperatures remaining around -10C.

On Monday, four natural size 1.5 storm slabs were observed in the Kootenay Pass area. These slabs were 10-20 cm thick. Ski cutting and explosives triggered numerous storm slabs size 1-1.5 throughout the region. These slabs were 10-30 cm thick and were failing on all aspects above around 1800 m elevation. On Wednesday, the recent snow is expected to remain reactive to human-triggering. Storm slabs may fail on a storm interface or could release a bit deeper on the widespread crust layer. Deeper instabilities in the snowpack also remain an isolated concern and storm slab avalanches could step down to a deeper layers resulting in very large avalanches.

At higher elevations, 30-50 cm of recent snow typically overlies a series of crust layers from mid-February. Recent reports suggest this snow is generally well bonded to the crust. On high north aspects, a layer of surface hoar from mid-February may sit below the recent snow and may still be reactive. In exposed terrain, recent southerly winds have scoured the new snow down to the crust and formed wind slabs in leeward features. The early-February surface hoar layer is now down approximately 80-100 cm. This layer was reactive during the warm storm last week but now appears to have gone dormant. Areas with a shallow snowpack (less than around 150 cm) generally have a weak snowpack structure with a layer of sugary facets near the ground.