About Flanagan, IL's Climate & Weather History

With a population of around 1,100, Flanagan sits in Illinois, United States. The city operates in the Central Time Zone.

In 2025, Flanagan recorded an average annual temperature of 53°F. The hottest temperatures reached 93°F in May; the coolest were -8°F in January. Total precipitation for the year was 31 inches, with the wettest month being July. Snowfall for the year totaled approximately 8 inches.