Canada wildfires are triggering air quality alerts in the U.S. again

Hotter, drier conditions, coupled with dry grasses and underbrush that accumulated over decades of fire suppression, have made large wildfires more common.

Dozens of wildfires are burning across Canada in May 2024 and sending unhealthy smoke blowing into the northern U.S. again. At the same time, the southeastern U.S. is getting smoke from Mexico, where drought conditions have been fueling fires.