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.

Partly Cloudy

28°F

-2°C

Humidity 75%
Wind Speed S 10 mph
Barometer 30.01 in
Dewpoint 21°F (-6°C)
Visibility 10.00 mi
Wind Chill19°F (-7°C)
Last update 5 Feb 7:35 pm CST
Extended Forecast for

Johnston City IL

  • Tonight

    Tonight: Partly cloudy, with a steady temperature around 31. West southwest wind 5 to 8 mph.

    Low: 31 °F

    Partly Cloudy

  • Friday

    Friday: Sunny during the morning, then mostly cloudy during the afternoon, with a high near 47. West southwest wind 6 to 11 mph becoming north northwest 12 to 17 mph in the afternoon. Winds could gust as high as 33 mph.

    High: 47 °F

    Partly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 24. North northwest wind 7 to 10 mph, with gusts as high as 18 mph.

    Low: 24 °F

    Mostly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 35. North northeast wind 5 to 7 mph becoming calm in the afternoon.

    High: 35 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 23. Calm wind becoming south southeast around 6 mph after midnight.

    Low: 23 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 49. South wind 5 to 8 mph.

    High: 49 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 29. Light and variable wind.

    Low: 29 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 55. Calm wind becoming south southwest around 5 mph.

    High: 55 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 40. South wind 3 to 6 mph.

    Low: 40 °F

    Mostly Clear

Detailed Forecast

Tonight
Partly cloudy, with a steady temperature around 31. West southwest wind 5 to 8 mph.
Friday
Sunny during the morning, then mostly cloudy during the afternoon, with a high near 47. West southwest wind 6 to 11 mph becoming north northwest 12 to 17 mph in the afternoon. Winds could gust as high as 33 mph.
Friday Night
Mostly cloudy, with a low around 24. North northwest wind 7 to 10 mph, with gusts as high as 18 mph.
Saturday
Sunny, with a high near 35. North northeast wind 5 to 7 mph becoming calm in the afternoon.
Saturday Night
Partly cloudy, with a low around 23. Calm wind becoming south southeast around 6 mph after midnight.
Sunday
Mostly sunny, with a high near 49. South wind 5 to 8 mph.
Sunday Night
Mostly clear, with a low around 29. Light and variable wind.
Monday
Sunny, with a high near 55. Calm wind becoming south southwest around 5 mph.
Monday Night
Mostly clear, with a low around 40. South wind 3 to 6 mph.
Tuesday
Partly sunny, with a high near 63. South southwest wind 6 to 9 mph.
Tuesday Night
A chance of showers. Cloudy, with a low around 46. South southwest wind around 7 mph.
Wednesday
A chance of showers. Mostly cloudy, with a high near 58. West southwest wind 7 to 9 mph.
Wednesday Night
A chance of showers. Mostly cloudy, with a low around 38. Southwest wind around 7 mph becoming west northwest after midnight.
Thursday
A chance of showers. Mostly cloudy, with a high near 51. West wind 7 to 9 mph becoming east in the morning.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.91°W
Last Update:
5:12 pm CST Feb 5, 2026
Forecast Valid:
7pm CST Feb 5, 2026-6pm CST Feb 12, 2026
 
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Additional Resources

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