The city had the worst air quality in the world on Wednesday, prompting health warnings and event cancellations. About 200 wildfires are burning in northwestern Ontario where First Nations communities have been ordered evacuated as smoke plumes stretch south across the U.S.-Canada border.

As of Tuesday night, just under 200 total active wildfires have been reported, according to the province.

Yellow-orange haze has blanketed Toronto since early Wednesday morning, as the impacts of raging wildfires in other parts of the province drift over with the wind.

Environment Canada has issued health warnings after sky over city turns yellow