About Long Grove, IL's Climate & Weather History

Long Grove, in Illinois, United States, is home to roughly 8,200 people in the Central Time Zone at 42.2°N latitude.

In 2025, Long Grove recorded an average annual temperature of 50°F — about 1.1°F below the 30-year normal of 51°F. The hottest day reached 94°F in August; the coldest was -10°F in February. Total precipitation was 34 inches (wetter than usual). The wettest month was June.