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

75°F

24°C

Humidity 99%
Wind Speed Calm
Barometer 29.93 in
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Last update 19 Aug 8:55 pm CDT
Extended Forecast for

2 Miles NW Johnston City IL

Flood Watch until August 20, 07:00am
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch until August 20, 07:00am

    NOW until 7:00am Thu

    Flood Watch

  • Tonight

    Low: 68 °F

    Showers
    Likely

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 3pm. Partly sunny, with a high near 86. Calm wind becoming north around 6 mph in the afternoon.

    High: 86 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 66. Light north wind.

    Low: 66 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly sunny, with a high near 88. Calm wind becoming north northwest around 5 mph in the afternoon.

    High: 88 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 66. Calm wind.

    Low: 66 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 88. Calm wind becoming northwest 5 to 9 mph in the afternoon.

    High: 88 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 65. Light north wind.

    Low: 65 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 87. Calm wind becoming north 5 to 8 mph in the afternoon.

    High: 87 °F

    Mostly Sunny

Detailed Forecast

Tonight
Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 68. Calm wind. Chance of precipitation is 70%.
Thursday
A 20 percent chance of showers and thunderstorms after 3pm. Partly sunny, with a high near 86. Calm wind becoming north around 6 mph in the afternoon.
Thursday Night
Increasing clouds, with a low around 66. Light north wind.
Friday
Mostly sunny, with a high near 88. Calm wind becoming north northwest around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 66. Calm wind.
Saturday
Mostly sunny, with a high near 88. Calm wind becoming northwest 5 to 9 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 65. Light north wind.
Sunday
Mostly sunny, with a high near 87. Calm wind becoming north 5 to 8 mph in the afternoon.
Sunday Night
A slight chance of showers. Partly cloudy, with a low around 64. Light east wind.
Monday
A slight chance of showers before 1pm. Mostly sunny, with a high near 86. Calm wind becoming southeast 5 to 7 mph in the morning.
Monday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 66. East southeast wind 3 to 6 mph.
Tuesday
Mostly sunny, with a high near 89. East southeast wind 5 to 8 mph.
Tuesday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 67. East wind around 5 mph becoming calm in the evening.
Wednesday
Mostly sunny, with a high near 91. Calm wind becoming northwest 5 to 7 mph in the morning.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles NW Johnston City IL
 37.85°N 88.94°W
Last Update:
8:56 pm CDT Aug 19, 2026
Forecast Valid:
9pm CDT Aug 19, 2026-6pm CDT Aug 26, 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