Avalanche Canada says the backcountry risk in the Kootenay/Boundary is considerable at and above the treeline and is expected to rise to high in the alpine on Thursday as another storm rolls in.
“Even right now as a baseline, we’re at pretty heightened avalanche conditions,” forecaster Ari Hanna says.
“We have two main problems on our hands. The first is the considerable amount of new storm snow we’re seen arrive. This recent snow is sitting over a potentially weak interface formed during the cold snap. We’re expecting reactivity to persist longer than usual.
“So come the weekend when skies are clearing up and everyone wants to get outside and enjoy the sun and new snow, we may still have a reactive storm slab problem on our hands.”
Hanna says the second issue is that all the new snow is adding more load to a deeply-buried weak layer that over the past week and a half has produced what she calls an “alarming pattern” of large avalanches throughout the region.
Some of those avalanches were triggered by skiers, “which is quite terrifying for those involved given the size.” Although the likelihood of triggering such a slide is low, doing so comes with “very high consequences,” Hanna said, adding that so far this winter everyone has survived.
Large avalanches have occurred around Nelson and Rossland. The incoming storm is expected to hit areas west of Castlegar on Thursday and the rest of the region on Friday.
“We need to be vigilant and have this problem at the front of our brains as we go out into the mountains,” she says.
Avalanche Canada’s latest forecast for the area, issued Tuesday, says “conservative terrain selection remains essential” for those who do venture in into the backcountry.