Hamilton, in Illinois, United States, is home to roughly 2,900 people in the Central Time Zone at 40.4°N latitude.
In 2025, Hamilton recorded an average annual temperature of 55°F — about 1.6°F above the 30-year normal of 53°F. The hottest day reached 95°F in June; the coldest was -8°F in January. Total precipitation was 28 inches (drier than usual). The wettest month was July.
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