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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

84°F

29°C

Humidity 66%
Wind Speed SW 5 mph
Barometer 30.08 in
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index89°F (32°C)
Last update 2 Sep 8:47 am CDT
Extended Forecast for

Marion IL

Extreme Heat Warning September 2, 09:34am until September 5, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning September 2, 09:34am until September 5, 08:00pm

    NOW until 8:00pm Sat

    Extreme Heat Warning

  • Today

    High: 99 °F

    Hot

  • Tonight

    Tonight: Clear, with a low around 76. South wind around 5 mph becoming calm in the evening.

    Low: 76 °F

    Clear

  • Thursday

    Thursday: Sunny and hot, with a high near 99. Heat index values as high as 105. Calm wind becoming southwest 5 to 7 mph in the afternoon.

    High: 99 °F

    Hot

  • Thursday Night

    Thursday Night: Clear, with a low around 76. Light and variable wind.

    Low: 76 °F

    Clear

  • Friday

    Friday: Sunny and hot, with a high near 99. Light and variable wind.

    High: 99 °F

    Hot

  • Friday Night

    Friday Night: Mostly clear, with a low around 76. Calm wind.

    Low: 76 °F

    Mostly Clear

  • Saturday

    Saturday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 98. Calm wind becoming northwest around 5 mph in the afternoon.

    High: 98 °F

    Sunny then
    Slight Chance
    T-storms

  • Saturday Night

    Saturday Night: A slight chance of showers before 1am. Partly cloudy, with a low around 70. Calm wind.

    Low: 70 °F

    Slight Chance
    Showers

Detailed Forecast

Today
Sunny and hot, with a high near 99. Southwest wind 3 to 8 mph.
Tonight
Clear, with a low around 76. South wind around 5 mph becoming calm in the evening.
Thursday
Sunny and hot, with a high near 99. Heat index values as high as 105. Calm wind becoming southwest 5 to 7 mph in the afternoon.
Thursday Night
Clear, with a low around 76. Light and variable wind.
Friday
Sunny and hot, with a high near 99. Light and variable wind.
Friday Night
Mostly clear, with a low around 76. Calm wind.
Saturday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 98. Calm wind becoming northwest around 5 mph in the afternoon.
Saturday Night
A slight chance of showers before 1am. Partly cloudy, with a low around 70. Calm wind.
Sunday
Sunny, with a high near 95. Calm wind becoming northeast 5 to 7 mph in the afternoon.
Sunday Night
Mostly clear, with a low around 69. East northeast wind around 6 mph becoming calm in the evening.
Labor Day
Sunny, with a high near 94. Calm wind becoming east 5 to 7 mph in the afternoon.
Monday Night
Partly cloudy, with a low around 68. East northeast wind around 6 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 94. Calm wind becoming south 5 to 8 mph in the morning.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Marion IL
 37.73°N 88.92°W
Last Update:
7:51 am CDT Sep 2, 2026
Forecast Valid:
9am CDT Sep 2, 2026-6pm CDT Sep 8, 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