As of Aug. 6, there are about 750 active Canadian wildfires, with at least 190 labeled “out of control,” according to the Canadian Interagency Forest Fire Centre. More than 16 million acres (6.8 million hectares) of land have been scorched this year, making this one of Canada’s worst wildfire seasons on record.

As Canada grapples with one of its worst wildfire seasons on record, smoke from the blazes have prompted air quality alerts across the U.S.

Canada is battling more than 700 active wildfires across the country, roughly two-thirds of which are burning out of control, according to the Canadian Interagency Forest Fire Center (CIFFC). Smoke billowing from the blazes has blanketed central Canada and the northern U.S., prompting widespread air quality alerts.