Weather forecast for: Caseyville IL
Last Update: 9:36 pm CDT Sep 11, 2026
Overnight: Patchy fog after 3am. Otherwise, partly cloudy, with a low around 69. Calm wind.
Saturday: Patchy fog before 8am. Otherwise, sunny, with a high near 91. Calm wind becoming west around 6 mph in the morning.
Saturday Night: Partly cloudy, with a low around 70. Light and variable wind.
Sunday: A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 90. Calm wind becoming north 5 to 7 mph in the afternoon. Chance of precipitation is 20%.
Sunday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 67. East wind 6 to 8 mph.
Monday: Mostly sunny, with a high near 89.
Monday Night: Mostly clear, with a low around 71.
Tuesday: Sunny, with a high near 96.
Tuesday Night: Partly cloudy, with a low around 72.
Wednesday: A slight chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 94. Chance of precipitation is 20%.
Wednesday Night: A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 72.
Thursday: A 40 percent chance of showers and thunderstorms. Mostly sunny, with a high near 89.
Thursday Night: A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 68.
Friday: A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 86.