Smoke from numerous Canadian wildfires is again impacting the Philadelphia region this week, with environmental authorities issuing code orange air quality alerts largely in effect through Tuesday as a result of the blazes’ aftermath settling in on the area.

Smoke from Canadian wildfires is causing air quality concerns for millions of Americans in the Midwest and Northeast.

Under a Code Orange alert, it's recommended that children, older adults and those with respiratory illnesses limit time spent outdoors.