An air quality alert remains in effect for the entire state of Minnesota on Monday. Smoke from Canadian wildfires prompted the alert, which is set to expire at 9 a.m. Tuesday. The northern half of the state will likely see the worst air quality.

An air quality alert was reported by the National Weather Service on Tuesday at 9:10 a.m. in effect until 11 p.m. for Western Chester, Eastern Chester, Western Montgomery, Eastern Montgomery, Upper Bucks and Lower Bucks as well as Delaware and Philadelphia counties.

An air quality alert will be in effect for all of Minnesota until at least 9 a.m. Aug. 12, according to the state Pollution Control Agency.