Rosemont, in Illinois, United States, is home to roughly 4,200 people in the Central Time Zone at 42°N latitude.
In 2025, Rosemont recorded an average annual temperature of 51°F — right at the 30-year normal of 51°F. The hottest day reached 96°F in June; the coldest was -9°F in February. Total precipitation was 36 inches (wetter than usual). The wettest month was June.
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