REVELSTOKE - A special avalanche warning has been issued for much of B.C. this weekend, with the Canadian Avalanche Centre saying slides are expected be much bigger than usual.

Avalanche forecaster Ilya Storm says the danger has been created by weak layers in the snowpack which can go down as far as two metres.

He says these have already resulted in larger, destructive avalanches that have run all the way to valley bottoms.

Storm says another danger is that slides can be triggered remotely, meaning a person can start a chain reaction which will cause an avalanche some distance away.

He says backcountry users should also be aware that slopes generally considered safer -- lower angle ones below the treeline -- are primed for slides triggered by human activity.

The avalanche warning is in effect until Sunday and covers the mountains of the Inland South Coast, the Columbia Mountains from Prince George to the U.S. border in the south, and B.C.'s southern Rockies.