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

45°F

7°C

Humidity 71%
Wind Speed W 9 mph
Barometer 30.26 in
Dewpoint 36°F (2°C)
Visibility 10.00 mi
Wind Chill40°F (4°C)
Last update 5 Apr 7:47 am CDT
Extended Forecast for

Johnston City IL

  • Today

    Today: Sunny, with a high near 60. Northwest wind 8 to 14 mph, with gusts as high as 21 mph.

    High: 60 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 39. North northwest wind around 6 mph becoming calm in the evening.

    Low: 39 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 67. Light west wind becoming northwest 5 to 9 mph in the morning.

    High: 67 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 41. North northeast wind 6 to 8 mph.

    Low: 41 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 57. East northeast wind 8 to 10 mph.

    High: 57 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 41. East wind around 6 mph.

    Low: 41 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 74. East southeast wind 6 to 11 mph becoming south in the afternoon. Winds could gust as high as 18 mph.

    High: 74 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 54. South wind 8 to 10 mph, with gusts as high as 21 mph.

    Low: 54 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 74. South wind 9 to 14 mph, with gusts as high as 22 mph.

    High: 74 °F

    Mostly Sunny

Detailed Forecast

Today
Sunny, with a high near 60. Northwest wind 8 to 14 mph, with gusts as high as 21 mph.
Tonight
Clear, with a low around 39. North northwest wind around 6 mph becoming calm in the evening.
Monday
Sunny, with a high near 67. Light west wind becoming northwest 5 to 9 mph in the morning.
Monday Night
Partly cloudy, with a low around 41. North northeast wind 6 to 8 mph.
Tuesday
Mostly sunny, with a high near 57. East northeast wind 8 to 10 mph.
Tuesday Night
Partly cloudy, with a low around 41. East wind around 6 mph.
Wednesday
Mostly sunny, with a high near 74. East southeast wind 6 to 11 mph becoming south in the afternoon. Winds could gust as high as 18 mph.
Wednesday Night
Partly cloudy, with a low around 54. South wind 8 to 10 mph, with gusts as high as 21 mph.
Thursday
Mostly sunny, with a high near 74. South wind 9 to 14 mph, with gusts as high as 22 mph.
Thursday Night
Partly cloudy, with a low around 56. South wind around 5 mph.
Friday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 78. South southwest wind 5 to 9 mph.
Friday Night
A slight chance of showers and thunderstorms. Mostly cloudy, with a low around 58. South wind around 6 mph.
Saturday
A chance of showers and thunderstorms. Partly sunny, with a high near 79. South wind 6 to 10 mph.
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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:
5:47 am CDT Apr 5, 2026
Forecast Valid:
8am CDT Apr 5, 2026-6pm CDT Apr 11, 2026
 
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Additional Resources

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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