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

55°F

13°C

Humidity 94%
Wind Speed Calm
Barometer 30.06 in
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 8 Oct 6:47 am CDT
Extended Forecast for

Johnston City IL

  • Today

    Today: Sunny, with a high near 85. Calm wind becoming east 5 to 7 mph in the morning.

    High: 85 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 55. Calm wind.

    Low: 55 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 88. South southeast wind 3 to 8 mph.

    High: 88 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 61. Southeast wind 3 to 5 mph.

    Low: 61 °F

    Mostly Clear

  • Saturday

    Saturday: A 40 percent chance of showers after 1pm. Partly sunny, with a high near 81. Light south southeast wind becoming east southeast 6 to 11 mph in the morning.

    High: 81 °F

    Partly Sunny
    then Chance
    Showers

  • Saturday Night

    Saturday Night: Showers. Low around 59. East wind 14 to 17 mph, with gusts as high as 20 mph. Chance of precipitation is 90%.

    Low: 59 °F

    Showers

  • Sunday

    Sunday: A 50 percent chance of showers before 1pm. Partly sunny, with a high near 74. East northeast wind 10 to 13 mph becoming west northwest in the afternoon.

    High: 74 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 57. Calm wind.

    Low: 57 °F

    Partly Cloudy

  • Columbus Day

    Columbus Day: Sunny, with a high near 86. Light southwest wind becoming south southwest 5 to 10 mph in the afternoon.

    High: 86 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 85. Calm wind becoming east 5 to 7 mph in the morning.
Tonight
Clear, with a low around 55. Calm wind.
Friday
Sunny, with a high near 88. South southeast wind 3 to 8 mph.
Friday Night
Mostly clear, with a low around 61. Southeast wind 3 to 5 mph.
Saturday
A 40 percent chance of showers after 1pm. Partly sunny, with a high near 81. Light south southeast wind becoming east southeast 6 to 11 mph in the morning.
Saturday Night
Showers. Low around 59. East wind 14 to 17 mph, with gusts as high as 20 mph. Chance of precipitation is 90%.
Sunday
A 50 percent chance of showers before 1pm. Partly sunny, with a high near 74. East northeast wind 10 to 13 mph becoming west northwest in the afternoon.
Sunday Night
Partly cloudy, with a low around 57. Calm wind.
Columbus Day
Sunny, with a high near 86. Light southwest wind becoming south southwest 5 to 10 mph in the afternoon.
Monday Night
Mostly clear, with a low around 61. South southwest wind around 8 mph.
Tuesday
A slight chance of showers. Sunny, with a high near 80. Northwest wind 9 to 14 mph.
Tuesday Night
A slight chance of showers. Mostly clear, with a low around 53. North northeast wind 5 to 8 mph.
Wednesday
Sunny, with a high near 75. East wind 5 to 8 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:
5:21 am CDT Oct 8, 2026
Forecast Valid:
7am CDT Oct 8, 2026-6pm CDT Oct 14, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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