National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Fair

88°F

31°C

Humidity 43%
Wind Speed SW 14 G 18 mph
Barometer 29.97 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Heat Index89°F (32°C)
Last update 12 Oct 1:45 pm CDT
Extended Forecast for

Johnston City IL

  • Columbus Day

    Columbus Day: Sunny, with a high near 91. Southwest wind 13 to 15 mph, with gusts as high as 20 mph.

    High: 91 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 66. South southwest wind around 8 mph.

    Low: 66 °F

    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 94. Southwest wind 6 to 11 mph.

    High: 94 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A slight chance of showers before 2am, then a slight chance of showers and thunderstorms after 4am. Mostly clear, with a low around 72. South southwest wind around 6 mph. Chance of precipitation is 20%.

    Low: 72 °F

    Clear then
    Slight Chance
    T-storms

  • Wednesday

    Wednesday: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 7am. High near 85. West southwest wind 5 to 7 mph. Chance of precipitation is 90%.

    High: 85 °F

    Showers

  • Wednesday Night

    Wednesday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 67. Calm wind. Chance of precipitation is 70%.

    Low: 67 °F

    Showers
    Likely

  • Thursday

    Thursday: Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 86. Light and variable wind becoming southwest 5 to 10 mph in the morning. Chance of precipitation is 60%.

    High: 86 °F

    Showers
    Likely

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms before 1am, then a slight chance of showers. Partly cloudy, with a low around 57. Southwest wind 6 to 15 mph becoming northwest after midnight.

    Low: 57 °F

    Chance
    T-storms

  • Friday

    Friday: Partly sunny, with a high near 67. Breezy, with a north northwest wind 20 to 22 mph, with gusts as high as 29 mph.

    High: 67 °F

    Partly Sunny
    and Breezy

Detailed Forecast

Columbus Day
Sunny, with a high near 91. Southwest wind 13 to 15 mph, with gusts as high as 20 mph.
Tonight
Clear, with a low around 66. South southwest wind around 8 mph.
Tuesday
Sunny, with a high near 94. Southwest wind 6 to 11 mph.
Tuesday Night
A slight chance of showers before 2am, then a slight chance of showers and thunderstorms after 4am. Mostly clear, with a low around 72. South southwest wind around 6 mph. Chance of precipitation is 20%.
Wednesday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 7am. High near 85. West southwest wind 5 to 7 mph. Chance of precipitation is 90%.
Wednesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 67. Calm wind. Chance of precipitation is 70%.
Thursday
Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 86. Light and variable wind becoming southwest 5 to 10 mph in the morning. Chance of precipitation is 60%.
Thursday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers. Partly cloudy, with a low around 57. Southwest wind 6 to 15 mph becoming northwest after midnight.
Friday
Partly sunny, with a high near 67. Breezy, with a north northwest wind 20 to 22 mph, with gusts as high as 29 mph.
Friday Night
Mostly clear, with a low around 41. North wind 8 to 18 mph, with gusts as high as 23 mph.
Saturday
Sunny, with a high near 63. Northeast wind 7 to 10 mph.
Saturday Night
Mostly clear, with a low around 38. Calm wind.
Sunday
Sunny, with a high near 71. Calm wind becoming south 5 to 8 mph in the morning.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.94°W
Last Update:
1:26 pm CDT Oct 12, 2026
Forecast Valid:
2pm CDT Oct 12, 2026-6pm CDT Oct 18, 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