About Sugar Grove, IL's Climate & Weather History

Sugar Grove is a city of approximately 9,500 people in Illinois, United States. Located in the Central Time Zone at 41.8°N latitude.

In 2025, Sugar Grove recorded an average annual temperature of 51°F — about 1.4°F above the 30-year normal of 49°F. The hottest day reached 93°F in May; the coldest was -10°F in February. Total precipitation was 33 inches (near normal). The wettest month was July.