Jacksonville is a city of approximately 19,100 people in Illinois, United States. Located in the Central Time Zone at 39.7°N latitude.
In 2025, Jacksonville recorded an average annual temperature of 55°F. The hottest temperatures reached 94°F in June; the coolest were -6°F in January. Total precipitation for the year was 32 inches, with the wettest month being July. Snowfall for the year totaled approximately 8 inches.
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