Northern Illinois and Northwest Indiana – Hazy skies from wildfire smoke will give way to a growing severe weather threat later today as thunderstorms organize along a cold front and move toward the Chicago area. While not everyone will see severe weather, any storm that develops could intensify quickly during the evening and overnight.
According to the National Weather Service in Chicago, damaging wind gusts up to 70 mph are the primary concern, although large hail, isolated tornadoes, and localized flash flooding remain possible. Forecasters note uncertainty in how widespread storms will become, but residents should closely monitor changing conditions through tonight.
One forecast scenario favors morning storms near the Iowa-Illinois border, which could limit the coverage of severe storms later today. A second, less likely scenario would allow greater instability to build, increasing the risk for more widespread severe weather across northern Illinois and northwest Indiana, including the potential for tornadoes.
The highest storm threat is expected to spread southeast through the evening. Current timing places the risk between 5 p.m. and 1 a.m. near Rockford, 7 p.m. to 3 a.m. across the Chicago metro including Aurora, Elgin, Joliet, and Kankakee, and 9 p.m. to 5 a.m. across northwest Indiana, including areas near Valparaiso and Rensselaer.
An Air Quality Alert remains in effect through today due to Canadian wildfire smoke, with unhealthy air possible across northern Illinois and northwest Indiana. Sensitive groups should reduce prolonged outdoor activity and monitor conditions at AirNow.gov.
Motorists along I-90, I-94, I-80, I-88, I-55, and I-57 should prepare for rapidly changing travel conditions after sunset, including heavy rain, strong wind gusts, and sharply reduced visibility.
Have multiple ways to receive weather warnings tonight, especially while sleeping, as additional watches and warnings may be issued if storms intensify.
