Colchester, in Illinois, United States, is home to roughly 1,300 people in the Central Time Zone at 40.4°N latitude.
In 2025, Colchester recorded an average annual temperature of 54°F. The hottest temperatures reached 96°F in June; the coolest were -8°F in January. Total precipitation for the year was 33 inches, with the wettest month being July. Snowfall for the year totaled approximately 8 inches.
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