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.

Overcast

63°F

17°C

Humidity 92%
Wind Speed Calm
Barometer 30.03 in
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Last update 22 May 12:35 am CDT
Extended Forecast for

Carterville IL

  • Overnight

    Overnight: Mostly cloudy, with a low around 59. East northeast wind around 5 mph.

    Low: 59 °F

    Mostly Cloudy

  • Friday

    Friday: Showers likely before 1pm, then showers likely and possibly a thunderstorm between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Cloudy, with a high near 73. East northeast wind around 7 mph. Chance of precipitation is 70%.

    High: 73 °F

    Chance
    Showers then
    Showers
    Likely

  • Friday Night

    Friday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 60. Northeast wind around 6 mph becoming calm in the evening. Chance of precipitation is 50%.

    Low: 60 °F

    Chance
    Showers

  • Saturday

    Saturday: Partly sunny, with a high near 80. Light west northwest wind.

    High: 80 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: A 20 percent chance of showers before 1am. Partly cloudy, with a low around 61. Calm wind.

    Low: 61 °F

    Slight Chance
    Showers

  • Sunday

    Sunday: A chance of showers, with thunderstorms also possible after 1pm. Mostly cloudy, with a high near 82. Light and variable wind. Chance of precipitation is 50%.

    High: 82 °F

    Chance
    Showers then
    Chance
    T-storms

  • Sunday Night

    Sunday Night: A slight chance of showers and thunderstorms, then a chance of showers after 1am. Mostly cloudy, with a low around 63. Calm wind. Chance of precipitation is 30%.

    Low: 63 °F

    Slight Chance
    T-storms then
    Chance
    Showers

  • Memorial Day

    Memorial Day: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 80. Calm wind becoming east around 5 mph in the afternoon.

    High: 80 °F

    Showers
    Likely

  • Monday Night

    Monday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 65. East wind around 5 mph becoming calm in the evening.

    Low: 65 °F

    Chance
    Showers

Detailed Forecast

Overnight
Mostly cloudy, with a low around 59. East northeast wind around 5 mph.
Friday
Showers likely before 1pm, then showers likely and possibly a thunderstorm between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Cloudy, with a high near 73. East northeast wind around 7 mph. Chance of precipitation is 70%.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 60. Northeast wind around 6 mph becoming calm in the evening. Chance of precipitation is 50%.
Saturday
Partly sunny, with a high near 80. Light west northwest wind.
Saturday Night
A 20 percent chance of showers before 1am. Partly cloudy, with a low around 61. Calm wind.
Sunday
A chance of showers, with thunderstorms also possible after 1pm. Mostly cloudy, with a high near 82. Light and variable wind. Chance of precipitation is 50%.
Sunday Night
A slight chance of showers and thunderstorms, then a chance of showers after 1am. Mostly cloudy, with a low around 63. Calm wind. Chance of precipitation is 30%.
Memorial Day
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 80. Calm wind becoming east around 5 mph in the afternoon.
Monday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 65. East wind around 5 mph becoming calm in the evening.
Tuesday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 82. East wind 3 to 7 mph.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 66. Southeast wind 3 to 6 mph.
Wednesday
Showers and thunderstorms likely. Partly sunny, with a high near 83. South southeast wind 5 to 7 mph.
Wednesday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 67. South southeast wind around 5 mph becoming calm in the evening.
Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 85. Calm wind becoming south around 6 mph in the afternoon.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Carterville IL
 37.76°N 89.09°W
Last Update:
10:21 pm CDT May 21, 2026
Forecast Valid:
12am CDT May 22, 2026-6pm CDT May 28, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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