Avalanche forecasters are warning that the cold, dry spells B.C. saw at the start of the ski season have created weak, unstable layers of snow in many parts of the province.
Ari Hannah, a forecaster with Avalanche Canada, said these kinds of conditions haven’t been seen since 2003 – a year with so many avalanche fatalities (29 across Canada) that the educational non-profit was created as a result.
Hannah said the problem many mountainous parts of B.C. are facing right now is the outcome of unusually dry weather seen at the beginning of winter. This created light, weak layers of snow, which have subsequently been buried 70 to 200 cm into the snowpack.
“When weak layers fail at this depth, the slab of snow on top of it breaks away and slides down the slope producing large avalanches.”
So far, Hannah said the risk has been highest in the central Columbias, Purcells, Kootenay Boundary and Lizard Range. There has also been some risk in the Cariboos and northern Rockies.
On Monday (Jan. 10), officials announced the conditions had claimed their first life. Two Nelson police officers were caught up in a slide near Kaslo while skiiing. One died and one remains in critical condition as of Tuesday, according to the Nelson Police Department.
Hannah said on average in Canada, around 10 people die in avalanches each year. The most common month for fatalities is March, when shifting weather increases the volatility of the snow.
Hannah said the risky conditions B.C. is seeing now will likely persist over the remainder of the season. Under them, the things most likely to trigger an avalanche include: a new, large snow fall, a heavy load landing on the snowpack, a sudden warming of temperatures, and a person moving about in shallower spots.
“Basically any rapid change to the snowpack is destabilizing and can trigger these layers to become more reactive again.”
Hannah said people should always be checking conditions before heading into the backcountry.
“It’s important to adopt a conservative mindset. You can still have fun while minimizing your risk.”