About Herrin, IL's Climate & Weather History

Herrin, in Illinois, United States, is home to roughly 12,900 people in the Central Time Zone at 37.8°N latitude.

In 2025, Herrin recorded an average annual temperature of 58°F — about 1.8°F above the 30-year normal of 56°F. The hottest day reached 96°F in July; the coldest was 2°F in February. Total precipitation was 43 inches (near normal). The wettest month was April.