Harrisburg, in Illinois, United States, is home to roughly 8,900 people in the Central Time Zone at 37.7°N latitude.
In 2025, Harrisburg recorded an average annual temperature of 58°F. The hottest temperatures reached 93°F in July; the coolest were 3°F in February. Total precipitation for the year was 47 inches, with the wettest month being April. Snowfall for the year totaled approximately 5 inches.
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