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Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Fair

78°F

26°C

Humidity 98%
Wind Speed SW 8 mph
Barometer 30.03 in
Dewpoint 77°F (25°C)
Visibility 10.00 mi
Heat Index81°F (27°C)
Last update 11 Aug 4:15 am CDT
Extended Forecast for

Marion IL

Heat Advisory August 11, 04:25am until August 13, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 11, 04:25am until August 13, 08:00pm

    NOW until 8:00pm Thu

    Heat Advisory

  • Today

    High: 97 °F

    Slight Chance
    Showers then
    Sunny

  • Tonight

    Tonight: A slight chance of showers before 4am, then a slight chance of showers and thunderstorms between 4am and 5am, then a slight chance of thunderstorms after 5am. Mostly clear, with a low around 78. South southwest wind 7 to 10 mph, with gusts as high as 18 mph. Chance of precipitation is 20%.

    Low: 78 °F

    Mostly Clear
    then Slight
    Chance
    T-storms

  • Wednesday

    Wednesday: A slight chance of showers before 8am, then a slight chance of showers and thunderstorms after 5pm. Sunny and hot, with a high near 98. Heat index values as high as 108. Southwest wind 6 to 9 mph. Chance of precipitation is 20%.

    High: 98 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 77. South southwest wind around 7 mph. Chance of precipitation is 20%.

    Low: 77 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: Mostly sunny, with a high near 96. West southwest wind 6 to 9 mph.

    High: 96 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 76. East southeast wind around 7 mph.

    Low: 76 °F

    Slight Chance
    T-storms

  • Friday

    Friday: Mostly sunny, with a high near 95. East northeast wind 3 to 6 mph.

    High: 95 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 75. East wind 3 to 6 mph.

    Low: 75 °F

    Mostly Clear

Detailed Forecast

Today
A slight chance of showers between 8am and 10am. Sunny and hot, with a high near 97. Heat index values as high as 105. Southwest wind 8 to 11 mph. Chance of precipitation is 20%.
Tonight
A slight chance of showers before 4am, then a slight chance of showers and thunderstorms between 4am and 5am, then a slight chance of thunderstorms after 5am. Mostly clear, with a low around 78. South southwest wind 7 to 10 mph, with gusts as high as 18 mph. Chance of precipitation is 20%.
Wednesday
A slight chance of showers before 8am, then a slight chance of showers and thunderstorms after 5pm. Sunny and hot, with a high near 98. Heat index values as high as 108. Southwest wind 6 to 9 mph. Chance of precipitation is 20%.
Wednesday Night
A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 77. South southwest wind around 7 mph. Chance of precipitation is 20%.
Thursday
Mostly sunny, with a high near 96. West southwest wind 6 to 9 mph.
Thursday Night
A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 76. East southeast wind around 7 mph.
Friday
Mostly sunny, with a high near 95. East northeast wind 3 to 6 mph.
Friday Night
Mostly clear, with a low around 75. East wind 3 to 6 mph.
Saturday
Sunny and hot, with a high near 98. South southwest wind 5 to 8 mph.
Saturday Night
Mostly clear, with a low around 77. South wind around 7 mph.
Sunday
Sunny and hot, with a high near 100. West wind 6 to 9 mph.
Sunday Night
Mostly clear, with a low around 75. West southwest wind around 6 mph becoming light and variable after midnight.
Monday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 92. North northwest wind 3 to 8 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Marion IL
 37.73°N 88.92°W
Last Update:
1:21 am CDT Aug 11, 2026
Forecast Valid:
4am CDT Aug 11, 2026-6pm CDT Aug 17, 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