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.

N/A

Humidity NA
Wind Speed NA
Barometer NA
Dewpoint N/A
Visibility NA
Last update *** Not a current observation ***
Extended Forecast for

Johnston City IL

  • Tonight

    Tonight: Increasing clouds, with a temperature rising to around 48 by 2am. South wind 3 to 7 mph.

    Low: 44 °F⇑

    Increasing
    Clouds

  • Friday

    Friday: Partly sunny, then gradually becoming sunny, with a high near 74. South southwest wind 7 to 13 mph, with gusts as high as 20 mph.

    High: 74 °F

    Becoming
    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 60. South southwest wind 8 to 11 mph.

    Low: 60 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 76. Southwest wind 11 to 16 mph, with gusts as high as 23 mph.

    High: 76 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 47. Southwest wind 6 to 10 mph becoming north northwest after midnight.

    Low: 47 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 61. North northwest wind 3 to 8 mph.

    High: 61 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 39. Calm wind.

    Low: 39 °F

    Mostly Clear

  • Monday

    Monday: A slight chance of showers after noon. Mostly sunny, with a high near 61. Calm wind becoming east southeast 5 to 9 mph in the morning.

    High: 61 °F

    Mostly Sunny
    then Slight
    Chance
    Showers

  • Monday Night

    Monday Night: Showers likely. Mostly cloudy, with a low around 49. East southeast wind 6 to 8 mph.

    Low: 49 °F

    Showers
    Likely

Detailed Forecast

Tonight
Increasing clouds, with a temperature rising to around 48 by 2am. South wind 3 to 7 mph.
Friday
Partly sunny, then gradually becoming sunny, with a high near 74. South southwest wind 7 to 13 mph, with gusts as high as 20 mph.
Friday Night
Mostly clear, with a low around 60. South southwest wind 8 to 11 mph.
Saturday
Mostly sunny, with a high near 76. Southwest wind 11 to 16 mph, with gusts as high as 23 mph.
Saturday Night
Partly cloudy, with a low around 47. Southwest wind 6 to 10 mph becoming north northwest after midnight.
Sunday
Sunny, with a high near 61. North northwest wind 3 to 8 mph.
Sunday Night
Mostly clear, with a low around 39. Calm wind.
Monday
A slight chance of showers after noon. Mostly sunny, with a high near 61. Calm wind becoming east southeast 5 to 9 mph in the morning.
Monday Night
Showers likely. Mostly cloudy, with a low around 49. East southeast wind 6 to 8 mph.
Tuesday
A chance of showers, mainly before noon. Partly sunny, with a high near 65. East southeast wind 8 to 11 mph becoming southwest in the morning.
Tuesday Night
A chance of showers. Mostly cloudy, with a low around 46. East southeast wind 3 to 7 mph.
Wednesday
A chance of showers. Mostly cloudy, with a high near 61. South wind 6 to 8 mph.
Wednesday Night
Showers likely. Cloudy, with a low around 49. South wind 5 to 8 mph.
Thursday
Showers likely. Mostly cloudy, with a high near 63. South wind 8 to 11 mph, with gusts as high as 18 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.94°W
Last Update:
9:51 pm CST Nov 13, 2025
Forecast Valid:
10pm CST Nov 13, 2025-6pm CST Nov 20, 2025
 
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Additional Resources

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High Temperature

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Chance of Precipitation