With a population of around 28,100, Oak Forest sits in Illinois, United States. The city operates in the Central Time Zone.
In 2025, Oak Forest recorded an average annual temperature of 51°F — about 1.0°F below the 30-year normal of 52°F. The hottest day reached 94°F in June; the coldest was -8°F in February. Total precipitation was 37 inches (wetter than usual). The wettest month was July.
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