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

Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Mostly Cloudy

77°F

25°C

Humidity 87%
Wind Speed SW 6 mph
Barometer 29.96 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 26 Aug 10:15 pm CDT
Extended Forecast for

Carterville IL

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly between 11pm and 1am. Partly cloudy, with a low around 67. Calm wind.

    Low: 67 °F

    Chance
    Showers

  • Thursday

    Thursday: Sunny, with a high near 88. Calm wind becoming north 5 to 8 mph in the afternoon.

    High: 88 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 64. Light north wind.

    Low: 64 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 88. Calm wind becoming north around 6 mph in the afternoon.

    High: 88 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 61. Light east wind.

    Low: 61 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 90. Light and variable wind.

    High: 90 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 65. Calm wind.

    Low: 65 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 93. Calm wind becoming south southwest 5 to 9 mph in the morning.

    High: 93 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 70. South wind 3 to 6 mph.

    Low: 70 °F

    Mostly Clear

Detailed Forecast

Tonight
A 30 percent chance of showers and thunderstorms, mainly between 11pm and 1am. Partly cloudy, with a low around 67. Calm wind.
Thursday
Sunny, with a high near 88. Calm wind becoming north 5 to 8 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 64. Light north wind.
Friday
Sunny, with a high near 88. Calm wind becoming north around 6 mph in the afternoon.
Friday Night
Mostly clear, with a low around 61. Light east wind.
Saturday
Sunny, with a high near 90. Light and variable wind.
Saturday Night
Mostly clear, with a low around 65. Calm wind.
Sunday
Sunny, with a high near 93. Calm wind becoming south southwest 5 to 9 mph in the morning.
Sunday Night
Mostly clear, with a low around 70. South wind 3 to 6 mph.
Monday
Sunny, with a high near 95. South southwest wind 5 to 10 mph.
Monday Night
Mostly clear, with a low around 73. South wind 3 to 6 mph.
Tuesday
Sunny, with a high near 96. Southwest wind 3 to 8 mph.
Tuesday Night
Mostly clear, with a low around 74. South southwest wind 3 to 6 mph.
Wednesday
Sunny, with a high near 96. Southwest wind 3 to 8 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Carterville IL
 37.76°N 89.09°W
Last Update:
9:16 pm CDT Aug 26, 2026
Forecast Valid:
10pm CDT Aug 26, 2026-6pm CDT Sep 2, 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