The Canadian Avalanche Centre is warning that large swaths of the mountainous areas of British Columbia and Alberta are at very high risk for avalanches this weekend.

The CAC issued the warning Saturday morning, saying the risk remains high until at least the end of Monday.

Karl Klassen, the manager of public avalanche warning services at the CAC, says the problem is that there are weak layers deeply buried in the snowpack.

"The nature of these layers is a bit of a mixed bag," he explained in the statement. "Different regions have different problems, but the fundamental concern applies across the board -- there's up to two metres of new snow sitting on some kind of fragile layer."

He explained that new, fallen snow has started to settle and so, while naturally-occurring avalanches are less likely, it also makes it easier for adventurers to travel further into the backcountry, possibly setting off a human-triggered avalanche

With clear skies forecast, many adventurers may be tempted to push into more aggressive terrain. Klassen said that could be "a deadly choice."

If avalanches are triggered, they are expected to be large, often running much farther than expected.

The warning applies to:

  • the Mountain National Parks (Rogers Pass, Banff, Yoho, Kootenay, Jasper and Waterton Lakes);
  • Alberta's Kananaskis Country
  • the South Coast Mountains east of Pemberton (Duffy Lake region)
  • the South Chilcotin Mountains (Bridge River, Carpenter Lake, Anderson Lake area)
  • the Columbia Mountains from the US border to Prince George
  • the North Rockies, north and east of Prince George (including areas around Mackenzie, Chetwynd, Pine Pass, Tumbler Ridge, and Kakwa Provincial Park)
  • the Southern Rockies forecast region

The CAC is urging all recreational backcountry users to stay away from large, steep and complex slopes. Recreationalists should stick to small, simple terrain below treeline, staying out of avalanche run-out zones, the CAC warns.

While officials admit they can't prevent people from heading into the backcountry, they maintain it's crucial that people know what they are in for if they decide to venture out.

They advise being prepared for an avalanche by being sure you have had basic avalanche training, and carrying beacons, probes and shovels.

Last week, extreme avalanche conditions in both Alberta and British Columbia led to three deaths. Two Calgary brothers were caught in a slide while backcountry skiing in Peter Lougheed Provincial Park, near the B.C.-Alberta border, while another Alberta man was killed by a slide near Nelson, B.C.

B.C. is seeing some of the worst avalanche conditions in 30 years. There have been more than 35 slides in the last month.