National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

A Few Clouds

66°F

19°C

Humidity 88%
Wind Speed Calm
Barometer 30.09 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 24 Aug 8:45 am CDT
Extended Forecast for

Carterville IL

  • Today

    Today: Sunny, with a high near 85. Light and variable wind.

    High: 85 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 63. Light east wind.

    Low: 63 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 87. Light east wind.

    High: 87 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 65. Calm wind.

    Low: 65 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 89. Calm wind becoming southwest around 5 mph in the afternoon.

    High: 89 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 68. Calm wind. Chance of precipitation is 20%.

    Low: 68 °F

    Slight Chance
    T-storms then
    Slight Chance
    Showers

  • Thursday

    Thursday: Sunny, with a high near 89. Calm wind becoming north northwest 5 to 8 mph in the afternoon.

    High: 89 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 65. Light north wind.

    Low: 65 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 89. Calm wind becoming north around 5 mph in the afternoon.

    High: 89 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 85. Light and variable wind.
Tonight
Mostly clear, with a low around 63. Light east wind.
Tuesday
Mostly sunny, with a high near 87. Light east wind.
Tuesday Night
Partly cloudy, with a low around 65. Calm wind.
Wednesday
Mostly sunny, with a high near 89. Calm wind becoming southwest around 5 mph in the afternoon.
Wednesday Night
A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 68. Calm wind. Chance of precipitation is 20%.
Thursday
Sunny, with a high near 89. Calm wind becoming north northwest 5 to 8 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 65. Light north wind.
Friday
Sunny, with a high near 89. Calm wind becoming north around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 66. Light and variable wind.
Saturday
Mostly sunny, with a high near 90. Calm wind becoming south around 5 mph in the afternoon.
Saturday Night
Partly cloudy, with a low around 69. Calm wind.
Sunday
Mostly sunny, with a high near 92. Calm wind becoming south southwest 5 to 8 mph in the morning.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Carterville IL
 37.76°N 89.09°W
Last Update:
4:01 am CDT Aug 24, 2026
Forecast Valid:
8am CDT Aug 24, 2026-6pm CDT Aug 30, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation