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.

Mostly Cloudy

54°F

12°C

Humidity 41%
Wind Speed SW 18 mph
Barometer 29.88 in
Dewpoint 30°F (-1°C)
Visibility 10.00 mi
Wind Chill49°F (9°C)
Last update 13 Jan 11:45 am CST
Extended Forecast for

Carterville IL

  • Today

    Today: Mostly sunny, with a high near 61. Southwest wind 10 to 14 mph, with gusts as high as 24 mph.

    High: 61 °F

    Mostly Sunny

  • Tonight

    Tonight: Showers likely, mainly between 11pm and 2am. Mostly cloudy, with a low around 41. Southwest wind 5 to 8 mph becoming west northwest after midnight. Chance of precipitation is 60%.

    Low: 41 °F

    Showers
    Likely

  • Wednesday

    Wednesday: Mostly cloudy, then gradually becoming sunny, with a temperature falling to around 34 by 5pm. Breezy, with a north northwest wind 8 to 13 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 29 mph.

    High: 46 °F⇓

    Mostly Cloudy
    then Mostly
    Sunny and
    Breezy

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 19. North northwest wind 6 to 15 mph, with gusts as high as 26 mph.

    Low: 19 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 32. Northwest wind 5 to 7 mph becoming light and variable in the afternoon.

    High: 32 °F

    Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of snow showers after midnight. Mostly cloudy, with a low around 24. Light south wind becoming south southwest 9 to 14 mph in the evening. Winds could gust as high as 23 mph.

    Low: 24 °F

    Partly Cloudy
    then Slight
    Chance Snow
    Showers

  • Friday

    Friday: Partly sunny, with a high near 46. West wind 11 to 14 mph, with gusts as high as 24 mph.

    High: 46 °F

    Partly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 23. West northwest wind around 10 mph, with gusts as high as 18 mph.

    Low: 23 °F

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 34. West northwest wind 9 to 14 mph, with gusts as high as 22 mph.

    High: 34 °F

    Partly Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 61. Southwest wind 10 to 14 mph, with gusts as high as 24 mph.
Tonight
Showers likely, mainly between 11pm and 2am. Mostly cloudy, with a low around 41. Southwest wind 5 to 8 mph becoming west northwest after midnight. Chance of precipitation is 60%.
Wednesday
Mostly cloudy, then gradually becoming sunny, with a temperature falling to around 34 by 5pm. Breezy, with a north northwest wind 8 to 13 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 29 mph.
Wednesday Night
Mostly clear, with a low around 19. North northwest wind 6 to 15 mph, with gusts as high as 26 mph.
Thursday
Sunny, with a high near 32. Northwest wind 5 to 7 mph becoming light and variable in the afternoon.
Thursday Night
A 20 percent chance of snow showers after midnight. Mostly cloudy, with a low around 24. Light south wind becoming south southwest 9 to 14 mph in the evening. Winds could gust as high as 23 mph.
Friday
Partly sunny, with a high near 46. West wind 11 to 14 mph, with gusts as high as 24 mph.
Friday Night
Mostly cloudy, with a low around 23. West northwest wind around 10 mph, with gusts as high as 18 mph.
Saturday
Partly sunny, with a high near 34. West northwest wind 9 to 14 mph, with gusts as high as 22 mph.
Saturday Night
Partly cloudy, with a low around 12. Northwest wind around 8 mph.
Sunday
Sunny, with a high near 27. West southwest wind 7 to 10 mph, with gusts as high as 18 mph.
Sunday Night
Mostly clear, with a low around 13. Southwest wind around 8 mph.
M.L.King Day
Sunny, with a high near 36. West wind 8 to 11 mph, with gusts as high as 20 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Carterville IL
 37.76°N 89.09°W
Last Update:
11:11 am CST Jan 13, 2026
Forecast Valid:
11am CST Jan 13, 2026-6pm CST Jan 19, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation