This advisory comes days after the Alberta Health Services issued a precautionary smoke advisory for Edmonton due to a lingering haze from forest fires burning hundreds of kilometres away.
Conditions are expected to improve somewhat on Sunday over southern Manitoba. Forecasters say some rainfall combined with shifting winds ahead of the system should help clear the air.
The smoky haze is expected to linger just a bit longer for areas further west of the province. A relatively slack wind regime combined with close proximity to the forest fires may prevent improvement for another couple of days.
People with respiratory or heart conditions are being advised to protect themselves from potential health risks linked to the current air conditions in and around Edmonton.
The advisory says even healthy people may experience irritation of the eyes and throat and possible shortness of breath.
A wildfire information officer says a wind blowing from the northwest is carrying smoke south from a fire near Zama City that has forced 200 people from their homes.
Health officials in Saskatchewan are also warning people about smoke from the Alberta fires, as well as from blazes in Saskatchewan and the Northwest Territories.
Suggestions include reducing physical activity when outside or staying indoors with windows closed.
With files from The Canadian Press