Parks Canada has issued a special avalanche warning after weeks of elevated risk and now a new snowfall and the appeal of clearing weather on the weekend.

Parks Canada visitor safety specialist Lisa Paulson says she can't stress enough how sensitive the avalanche conditions are.

"Things are so touchy, even just a few days ago we had a couple of skiers in the out of bounds area at Sunshine on a feature called Quartz Ridge, and they triggered the slope from 30 metres away," Paulson said.

The warning is in place Friday through Monday and it's widespread — targeting hikers, skiers and other backcountry users in Banff, Jasper, Yoho, Glacier, Mount Revelstoke and Kananaskis Country parks.

Avalanche Canada has also issued a special warning for ranges in the interior.

While the weather is set to be beautiful and sunny over the weekend, Paulson said now is not the time to head out into the backcountry.

"The name of the game this weekend is conservative route selection, low angle terrain,and being very mindful of overhead hazard," she said, adding that visitor centres would be able to recommend safer routes for those that are still hoping to enjoy the outdoors.

Parks Canada said large avalanches have been travelling into valley bottoms in recent weeks and the risk will continue though the weekend.

"People might be surprised by how large an avalanche can be triggered and how far it could run," said Mark Bender, a forecaster for Avalanche Canada, in a release.