With a population of around 4,000, Caseyville sits in Illinois, United States. The city operates in the Central Time Zone.
In 2025, Caseyville recorded an average annual temperature of 56°F — right at the 30-year normal of 57°F. The hottest day reached 95°F in July; the coldest was 0°F in February. Total precipitation was 43 inches (wetter than usual). The wettest month was April.
View current conditions and forecast for Caseyville · More cities in Illinois