Almost the entire southern half of Minnesota will have air quality unhealthy for some people on Friday, the Minnesota Pollution Control Agency says.
The cause: unseasonably high temps, sunny skies and bad air moving from the southern and central U.S., the MPCA said in a statement.
It'll be the second day in a row that the Twin Cities and St. Cloud metro areas have had poor air quality.
People with breathing conditions and children are most likely to experience problems from the bad air.
The bad air moving in from the south is what's considered "bad" ozone.
Ozone is good higher in the air for protecting us from the sun's rays, the MPCA said. "But down here, where we live and breathe, it's called ground-level ozone. And having too much of it can be harmful to human health."