Kootenay Boundary

30 to 60 cm of snow is slowly coalescing into a slab above the mid-February persistent weak layer that has recently been sensitive to human triggering. Watch for fresh wind stiffened storm slabs, especially at upper elevations.

Low - Timing, track, or intensity of incoming weather system is uncertain on Thursday

After much uncertainty, the models have converged on a solution that is more of a glancing blow than direct hit, but the Kootenay Boundary should see consistent dribs and drabs of precipitation Wednesday night through early Saturday morning. It looks like we will be entering a high and dry period beginning Sunday. WEDNESDAY NIGHT: Freezing level at valley bottom, strong wind mainly out of the south, 2 to 10 cm of snow.THURSDAY: Overcast, freezing level rising to around 1300 m, moderate southeast wind, 2 to 10 cm of snow during the day with another 2 to 10 cm possible Thursday night. FRIDAY: Broken cloud cover, freezing level around 1000 m, light variable wind, 1 to 5 cm of snow possible.SATURDAY: Scattered cloud cover, freezing level around 1100 m, light variable wind, no precipitation expected.

Relatively deep storm slabs were sensitive to human triggering on Tuesday to size 1.5 on south and east facing terrain between 1700 and 2000 m. Crown heights were between 25 and 60 cm. Widespread sluffing was also reported.On Monday control work produced wind slab avalanches to size 1 on south and east facing features around 2150 m. A skier triggered size 1.5 avalanche was reported on a southwest facing feature at 2000 m which likely ran on the February 23rd sun crust that was buried by the recent storm. Loose dry avalanches to size 1 were also reported from northwest through northeast facing terrain between 2000 and 2100 m. On Sunday storm slab avalanches were susceptible to both skier triggering and explosive control work to size 2. Storm slabs were reported from an east facing slope at 2025 m and northeast through northwest facing slopes between 1900 and 2100 m. In the southern portion of the neighboring South Columbia region a skier triggered size 2 avalanche was reported from a southwest facing slope at 1550 m. The avalanche had a crown 40 to 60 cm in depth and ran on the mid-February weak layer.

The region picked up 20 to 35 cm of new snow Tuesday and Wednesday which adds to the two successive storms over the weekend that produced 10 to 40 cm of new snow. The weekend storm was accompanied by wind out of the southwest, west and northwest. In some locations this snow rests on the February 23rd weak layer which is composed of small surface hoar on polar aspects and a thin crust on solar aspects. 30 to 60 cm of snow now rests on the mid-February weak layer that is composed of facets, surface hoar and a sun crust on solar aspects.Deeper in the snowpack weak layers that formed in January and December are gradually gaining strength. Several surface hoar and facet layers are buried 1 to 2 m below the surface and there is a crust/ facet interface near the base of the snowpack. No avalanches have been reported on these layers for the past two weeks and snowpack tests are showing improved bonding. Despite these signs, avalanche professionals are still treating these layers with respect and being cautious around shallow start zones and big avalanche paths.