Air quality gradually improving in northern Illinois

An air quality alert once again is in effect until midnight Friday for Will, McHenry, Kane, DeKalb, Ogle, Kendall, La Salle and DuPage counties in northern Illinois, said Scott Baker, meteorologist, at the National Weather Service Chicago.

Even with the alert, the air quality in the region is gradually improving, from very unhealthy Wednesday to unhealthy Thursday, according to AirNow.gov.

The hope is that the upcoming rain might continue improving air quality, Baker said. “But in terms of completely removing the smoke, it’s questionable. We just have to wait and see how this system progresses through.”

A line of showers and thunderstorms is expected to move into the area over the few hours, mostly south of Interstate 88, Baker said at noon on Thursday.

A second round will occur in the evening, mainly north of Interstate 80, Baker said. The main threats with these storms are damaging winds and the potential for hail. “And we cannot rule out the possibility of a tornado or two.”

“We cannot rule out the possibility of a tornado or two.”

—  Scott Baker, meteorologist, National Weather Service Chicago

It’s also possible the Illinois Environmental Protection Agency will extend the air quality alert, Baker said. But that’s difficult to determine until the storms push through the area, which they should do by midnight.

“Hopefully, there will be a reevaluation after that to see if anything is needed for a continuation into tomorrow,” Baker said.

Smoke from Canadian wildfires currently is the main cause of the region’s unhealthy air quality.

[ How to stay safe during unhealthy air quality ]

Dr. Kalisha Hill, regional chief medical officer for Ascension Saint Joseph-Joliet and Ascension Saint Mary-Kankakee, said Wednesday that the smoke is just a small part of the “burning material.”

The tiny particles traveling south from the wildfires in Canada may include any material lingering in the air, from burning wood to metal from cars, Hill said. The U.S. Environmental Protection Agency said these particles “can travel deep into the lungs and may even enter the bloodstream.”

When air quality is unhealthy, people in sensitive groups should avoid outdoor physical activity, according to AirNow. Sensitive groups include people with heart or lung disease, as well as “older adults, children and teenagers, minority populations and outdoor workers.”

Everyone else should avoid strenuous outdoor activity, take frequent breaks and reduce the amount of time they spend outside, according to AirNow. All people should consider staying inside as much as possible.