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.

Fair

47°F

8°C

Humidity 92%
Wind Speed Calm
Barometer 30.07 in
Dewpoint 45°F (7°C)
Visibility 10.00 mi
Last update 14 May 2:55 am CDT
Extended Forecast for

Marion IL

  • Overnight

    Overnight: Clear, with a steady temperature around 50. Calm wind.

    Low: 50 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 77. Calm wind.

    High: 77 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 54. Calm wind becoming south southeast around 6 mph after midnight.

    Low: 54 °F

    Mostly Clear

  • Friday

    Friday: A 40 percent chance of showers and thunderstorms, mainly before 10am. Mostly cloudy, then gradually becoming sunny, with a high near 83. South wind 8 to 14 mph, with gusts as high as 23 mph.

    High: 83 °F

    Chance
    Showers then
    Mostly Sunny

  • Friday Night

    Friday Night: A chance of showers and thunderstorms between 1am and 4am, then a chance of showers after 4am. Mostly cloudy, with a low around 67. South wind 8 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.

    Low: 67 °F

    Mostly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: A chance of showers, with thunderstorms also possible after 7am. Partly sunny, with a high near 86. South southwest wind 10 to 13 mph, with gusts as high as 22 mph. Chance of precipitation is 30%.

    High: 86 °F

    Chance
    Showers

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 67. South wind 6 to 9 mph, with gusts as high as 21 mph.

    Low: 67 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 90. South wind 6 to 15 mph, with gusts as high as 22 mph.

    High: 90 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 69. South wind 8 to 11 mph, with gusts as high as 22 mph.

    Low: 69 °F

    Mostly Clear

Detailed Forecast

Overnight
Clear, with a steady temperature around 50. Calm wind.
Thursday
Sunny, with a high near 77. Calm wind.
Thursday Night
Mostly clear, with a low around 54. Calm wind becoming south southeast around 6 mph after midnight.
Friday
A 40 percent chance of showers and thunderstorms, mainly before 10am. Mostly cloudy, then gradually becoming sunny, with a high near 83. South wind 8 to 14 mph, with gusts as high as 23 mph.
Friday Night
A chance of showers and thunderstorms between 1am and 4am, then a chance of showers after 4am. Mostly cloudy, with a low around 67. South wind 8 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.
Saturday
A chance of showers, with thunderstorms also possible after 7am. Partly sunny, with a high near 86. South southwest wind 10 to 13 mph, with gusts as high as 22 mph. Chance of precipitation is 30%.
Saturday Night
Partly cloudy, with a low around 67. South wind 6 to 9 mph, with gusts as high as 21 mph.
Sunday
Sunny, with a high near 90. South wind 6 to 15 mph, with gusts as high as 22 mph.
Sunday Night
Mostly clear, with a low around 69. South wind 8 to 11 mph, with gusts as high as 22 mph.
Monday
A slight chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. South wind 10 to 18 mph, with gusts as high as 28 mph.
Monday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 73. South wind 10 to 15 mph, with gusts as high as 24 mph.
Tuesday
Showers and thunderstorms likely. Partly sunny, with a high near 84. South southwest wind 9 to 16 mph, with gusts as high as 24 mph.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 67. South wind 5 to 10 mph, with gusts as high as 21 mph.
Wednesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 82. South southwest wind around 8 mph becoming west in the afternoon.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Marion IL
 37.73°N 88.92°W
Last Update:
2:11 am CDT May 14, 2026
Forecast Valid:
3am CDT May 14, 2026-6pm CDT May 20, 2026
 
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Additional Resources

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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