About Mount Carroll, IL's Climate & Weather History

With a population of around 1,600, Mount Carroll sits in Illinois, United States. The city operates in the Central Time Zone.

In 2025, Mount Carroll recorded an average annual temperature of 50°F. The hottest temperatures reached 93°F in June; the coolest were -12°F in February. Total precipitation for the year was 33 inches, with the wettest month being August. Snowfall for the year totaled approximately 9 inches.