How bad is the air quality in Chicago today?

It’s the worst anywhere on the planet, according to the World Air Quality Index. That’s right — worse than the biggest, most polluted cities in India and China. Minneapolis was ranked second; Detroit fifth.

Airquality.gov, which uses the official U.S. Air Quality Index, listed Chicago as “unhealthy” as of 9 a.m. Chicago time.

Blame the wildfire smoke north of the border in Canada.

“Definitely people with respiratory issues should definitely limit their time outdoors today and try to maintain themselves indoors if at all possible,” said Zachary Yack, a meteorologist with the National Weather Service in Romeoville.

The Weather Service doesn’t issue air quality alerts, although it does post them from local and state agencies, Yack said. Illinois had not issued an air quality alert as of 9:20 a.m., Yack said.

The Chicago Department of Public Health was in the process of drafting a statement on the city’s air quality, a spokesman told the Chicago Sun-Times on Tuesday morning.

Chicago Public Schools issued a statement Tuesday concerning CPS summer programs: CPS “will be using plans for inclement weather and will be holding programs indoors today to reduce the risk to students and staff.”

Yack noted that winds Tuesday have been pulling the smoke from Canada across Wisconsin, Michigan and portions of Illinois and northern Indiana.

“The smoke is expected to kind of gradually push south and westward through the day today and thin as it does so. Unfortunately, it looks like we’re going to be in this smoky haze through at least tonight and then into the early part of tomorrow before things really start to improve,” Yack said.