The smoke is expected to remain over the northern and central Plains of the United States for the next couple of days, according to meteorologists.

Out with the heat, in with the smoke.Just as Toronto's fifth heat warning this year was lifted, Environment Canada issued a special air quality statement for the city Wednesday night.The statement is the result of smoke from forest fires over the Prairies drifting into southern Ontario,

Health experts are not currently concerned about air quality in Toronto but warn prolonged exposure to moderate risk air may threaten health.