September weather forecast and climate
Illinois, USA

Flag of Illinois, USA
Flag of Illinois, USA

Weather in September

September brings the beautiful fall season to Illinois with comfortable conditions and dazzling colors. The daily sunlight of 8 hours peaks in the afternoon, while the humidity is at the highest in the mornings. The average temperatures are in the pleasant 50°F (10°C) to 80°F (26.7°C) range across the state, with 3" (76mm) to 4" (102mm) of rainfall.
The maples, elms, and walnuts change colors by mid-September as the landscape assumes a fairyland look. By the end of September, the hues are prominent with brilliant shades of red, orange, yellow, purple, and magenta. An autumn weekend is ripe to experience a fall color festival. Colors run amok from rural farming towns to urban metropolitan areas and their suburbs. Fall evenings are perfect for romantic settings in a natural environment untouched by time.
Light jackets provide comfort during the breezy evenings, while t-shirts are suitable during the day when the temperatures are high. September is one of the best times to visit Illinois.


Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location
* you will be automatically redirected to the weather forecast for your location