Prolific smoke that’s blown across North America and beyond over the past couple of weeks will bring reduced air quality to southern Ontario through Saturday, with an improvement expected on Sunday. DON’T MISS: Best practices to keep yourself safe from wildfire smoke Significant wildfire activity across the western half of the country has sent plumes of smoke from the Arctic to the tropics—and even across the pond toward Europe.

Smoke from wildfires burning in northern Ontario and the Prairies of Canada caused poor air quality and reduced visibility in major cities including Toronto, Ottawa and Montreal on Friday.