Canadian officials say warm, dry weather over the weekend has sparked more wildfires in Saskatchewan, while lightning ignited more fires in British Columbia.

Thousands of people have been evacuated because of the hundreds of fires burning across Canada's western provinces and the thick smoke they produce. Air advisories have been issued across central and western Canada, as well as parts of the western U.S.

Steve Roberts, a wildfire management official in the province of Saskatchewan, said Monday that cooler temperatures are expected to arrive over the next few days. If they are accompanied by strong winds, it will help dissipate some of the thick smoke.

Some 1,500 personnel fighting fires in Saskatchewan include members of the Canadian military, along with nearly 60 specialized U.S. firefighters from various states.