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.

Partly Cloudy

63°F

17°C

Humidity 88%
Wind Speed S 12 mph
Barometer 29.93 in
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Last update 7 Mar 1:45 pm CST
Extended Forecast for

Johnston City IL

  • This Afternoon

    This Afternoon: Showers and thunderstorms likely, mainly before 4pm. Mostly cloudy, with a steady temperature around 62. South southwest wind around 11 mph becoming west northwest. Winds could gust as high as 21 mph. Chance of precipitation is 60%.

    High: 62 °F

    Showers
    Likely

  • Tonight

    Tonight: Mostly cloudy, with a low around 40. West northwest wind 6 to 11 mph becoming light northwest after midnight.

    Low: 40 °F

    Mostly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 66. Calm wind becoming west southwest around 6 mph in the afternoon.

    High: 66 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 46. South wind around 6 mph.

    Low: 46 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 74. South southwest wind 6 to 15 mph, with gusts as high as 23 mph.

    High: 74 °F

    Sunny

  • Monday Night

    Monday Night: A slight chance of showers and thunderstorms between midnight and 3am, then a slight chance of showers after 3am. Partly cloudy, with a low around 62. South southwest wind 9 to 14 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.

    Low: 62 °F

    Partly Cloudy
    then Slight
    Chance
    T-storms

  • Tuesday

    Tuesday: A 40 percent chance of showers and thunderstorms after noon. Mostly cloudy, with a high near 79. South southwest wind 9 to 16 mph, with gusts as high as 24 mph.

    High: 79 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after midnight. Cloudy, with a low around 62. Breezy, with a south southwest wind 15 to 20 mph, with gusts as high as 28 mph.

    Low: 62 °F

    Chance
    T-storms and
    Breezy then
    Showers
    Likely

  • Wednesday

    Wednesday: Showers and possibly a thunderstorm. Cloudy, with a high near 73. South southwest wind 16 to 18 mph becoming northwest in the afternoon. Winds could gust as high as 29 mph.

    High: 73 °F

    Showers

Detailed Forecast

This Afternoon
Showers and thunderstorms likely, mainly before 4pm. Mostly cloudy, with a steady temperature around 62. South southwest wind around 11 mph becoming west northwest. Winds could gust as high as 21 mph. Chance of precipitation is 60%.
Tonight
Mostly cloudy, with a low around 40. West northwest wind 6 to 11 mph becoming light northwest after midnight.
Sunday
Sunny, with a high near 66. Calm wind becoming west southwest around 6 mph in the afternoon.
Sunday Night
Clear, with a low around 46. South wind around 6 mph.
Monday
Sunny, with a high near 74. South southwest wind 6 to 15 mph, with gusts as high as 23 mph.
Monday Night
A slight chance of showers and thunderstorms between midnight and 3am, then a slight chance of showers after 3am. Partly cloudy, with a low around 62. South southwest wind 9 to 14 mph, with gusts as high as 22 mph. Chance of precipitation is 20%.
Tuesday
A 40 percent chance of showers and thunderstorms after noon. Mostly cloudy, with a high near 79. South southwest wind 9 to 16 mph, with gusts as high as 24 mph.
Tuesday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after midnight. Cloudy, with a low around 62. Breezy, with a south southwest wind 15 to 20 mph, with gusts as high as 28 mph.
Wednesday
Showers and possibly a thunderstorm. Cloudy, with a high near 73. South southwest wind 16 to 18 mph becoming northwest in the afternoon. Winds could gust as high as 29 mph.
Wednesday Night
A chance of showers before midnight. Partly cloudy, with a low around 35. Northwest wind 15 to 18 mph, with gusts as high as 26 mph.
Thursday
Sunny, with a high near 56. Northwest wind 6 to 14 mph, with gusts as high as 20 mph.
Thursday Night
Mostly cloudy, with a low around 41. South wind 5 to 13 mph, with gusts as high as 21 mph.
Friday
Partly sunny, with a high near 67. Southwest wind 14 to 18 mph, with gusts as high as 28 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:
2:07 pm CST Mar 7, 2026
Forecast Valid:
2pm CST Mar 7, 2026-6pm CDT Mar 13, 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