A non-profit organization dedicated to public avalanche safety is warning British Columbians of “extreme” risk in parts of the province on Tuesday.
Avalanche Canada expects the atmospheric river beginning Tuesday will bring “very dangerous conditions, with the potential for full path avalanches,” the service tweeted Monday evening.
In an interview Tuesday, the organization’s forecasting program supervisor said those avalanches may be “extremely large and destructive,” reaching valley bottoms that are normally considered safe.
“We’re seeing the third of these atmospheric rivers coming back to back,” James Floyer told Global News. “That’s really given us just a huge amount of accumulation of snow.”
Rising temperatures and rain in the valleys and mountains combined with high winds means British Columbians should think twice about recreating near some of their favourite mountains, he added.
“You put it all together and you’ve got everything you need for a very serious avalanche cycle to happen.”
An avalanche forecast provides danger ratings for alpine, treeline and below treeline land. Each level of terrain can have its own rating.
In northern B.C., Avalanche Canada’s areas of “extreme” or “high” risk include the coast north of Kitimat and the Interior north of Hazelton, along with the North Rockies above Prince George, and the Cariboo Mountains.
In the southern part of the province, the same level of risk is attached to the Sea to Sky region, South Coast Inland, South Columbia, Purcells, North Columbia, and the Kootenay Boundary region west of Castlegar.
The danger may carry into Wednesday, Floyer warned.
Parks Canada forecasts the alpine risk to be extreme on Wednesday at the alpine level in B.C.’s Glacier National Park, northeast of Revelstoke, while the treeline and below-treeline risks are high.
On Thursday, danger ratings at the alpine and treeline levels will be downgraded from extreme to high, while the risk below treelines will be considerable.
The atmospheric river is expected to pass between Wednesday and Friday, and Floyer said Friday would be a “great time” to check Avalanche Canada’s website for an updated forecast.
“We could be in reasonable shape for the weekend provided we’re not seeing subsequent storm systems come through in the region,” he said.
Meanwhile, Avalanche Canada is urging backcountry recreationalists in southwestern B.C. to respect the province’s non-essential travel restrictions, and encouraging them to consider donating to flood relief fundraisers, such as that of the Red Cross.