A winter storm has created unstable avalanche conditions around Cranbrook and Kimberley.
An avalanche expert is warning people planning to hit backcountry slopes in eastern British Columbia and western Alberta in the coming days to be extra careful.
Karl Klassen says a major storm tracking across the region could dump up to 50 centimetres of snow on mountains and hills in some areas that are already covered by weak layers.
Klassen says avalanche forecasters are concerned that snowmobilers, skiers and snowboarders might be lulled into a false sense of security after a few years of stable conditions.
"We are asking people to be a bit more cautious this year than they were last year,'' Klassen, warning services manager for the Canadian Avalanche Centre in Revelstoke, said Thursday.
"Take on smaller slopes that aren't as complex, slopes that aren't as steep.''
The avalanche hazard prompted the B.C. government to close a 45-kilometre stretch of the Trans-Canada Highway from Craigellachie to Revelstoke in both directions until at least Friday morning. Traffic was being diverted to safer routes.
The Kootenay Pass on Highway 3 was closed part of Friday morning for snow removal and avalanche control.
There have been three serious avalanches in the Golden area in the past two weeks, including one on Dec. 20 that killed an Edmonton man who was snowboarding out of bounds at a ski resort.
In another avalanche Dec. 29, two of four people backcountry skiing near the Alberta boundary were injured, one of them seriously. The four were flown out of the area the next day by helicopter.
There was another avalanche in the area on Dec. 31 in which a person was seriously hurt.
Klassen said forecasters hope that the recent avalanches don't mark the start of a trend this season.
"The layers of snow are just waiting for the wind and snow to overload them and cause avalanches,'' he said.
"If it doesn't happen naturally, it is almost certainly going to happen if a skier or a snowmobile touches the wrong place on the wrong slope at the wrong time.''
Around Cranbrook and Kimberley, most of the backcountry was rated at a high risk of avalanche over the weekend.
In the Purcells region, which covers west of Kimberley and north to Golden, the risk is high in the alpine and treeline, and considerable below treeline.
In the South Rockies – east of Kimberley and Cranbrook to the Alberta border, the risk is also high in the alpine and treeline, and considerable below treeline.
In the Kootenay Boundary region, which covers south of Cranbrook and over to the West Kootenay, the risk is considerable at alpine and treeline, and moderate below treeline.
High risk means there are very dangerous avalanche conditions. Travel in avalanche terrain is not recommended.
Klassen said people venturing out need to check local avalanche and weather conditions. They should also carry emergency equipment such as transceivers, probes and shovels and be properly trained in how to use them.
Being less aggressive on the slopes in such conditions could make all the difference, he suggested.
"We want to remind people that this year isn't like last year or the year before. You need to be really doing your homework and ensure you are approaching slopes with caution to make sure you don't trigger one of these weak layers that are hidden from view right now.''
With files from Canadian Press