About River Grove, IL's Climate & Weather History

With a population of around 10,200, River Grove sits in Illinois, United States. The city operates in the Central Time Zone.

In 2025, River Grove recorded an average annual temperature of 51°F — about 1.1°F below the 30-year normal of 52°F. The hottest day reached 97°F in June; the coldest was -9°F in February. Total precipitation was 35 inches (near normal). The wettest month was June.