Wildfires raging in Canada could send smoke clouds to Washington, D.C., as soon as Thursday, creating dangerous air quality levels for millions.

Meteorologists said the district and other areas across the mid-Atlantic and Northeast could see smoky conditions as soon as Wednesday, July 15. The Washington, D.C., area could receive a “light to moderate impact” from the Canadian wildfires on Wednesday, FOX 5 chief meteorologist Tucker Barnes said.