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Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Partly Cloudy

18°C

64°F

Humidity 68%
Wind Speed NE 9 km/h
Barometer 30.15 in
Dewpoint 12°C (54°F)
Visibility 16 km
Last update 14 Sep 3:55 am CDT
Extended Forecast for

Marion IL

Heat Advisory September 15, 11:00am until September 16, 07:00pm
Click here for hazard details and duration
Heat Advisory

  • Today

    Today: Sunny, with a high near 31. East wind around 14 km/h.

    High: 31 °C

    Sunny

  • Tonight

    Tonight: Clear, with a low around 21. East wind 8 to 11 km/h.

    Low: 21 °C

    Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 36. Heat index values as high as 41. South southwest wind 8 to 14 km/h.

    High: 36 °C

    Hot

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 23. Calm wind.

    Low: 23 °C

    Mostly Clear

  • Wednesday

    Wednesday: Sunny and hot, with a high near 36. Light south southeast wind becoming south southwest 6 to 11 km/h in the morning.

    High: 36 °C

    Hot

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 23. Calm wind.

    Low: 23 °C

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 35. Calm wind becoming west southwest 5 to 10 km/h in the morning.

    High: 35 °C

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 22. Calm wind.

    Low: 22 °C

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 34. Calm wind becoming southwest 5 to 10 km/h in the morning.

    High: 34 °C

    Sunny

Detailed Forecast

Today
Sunny, with a high near 31. East wind around 14 km/h.
Tonight
Clear, with a low around 21. East wind 8 to 11 km/h.
Tuesday
Sunny and hot, with a high near 36. Heat index values as high as 41. South southwest wind 8 to 14 km/h.
Tuesday Night
Mostly clear, with a low around 23. Calm wind.
Wednesday
Sunny and hot, with a high near 36. Light south southeast wind becoming south southwest 6 to 11 km/h in the morning.
Wednesday Night
Mostly clear, with a low around 23. Calm wind.
Thursday
Sunny, with a high near 35. Calm wind becoming west southwest 5 to 10 km/h in the morning.
Thursday Night
Mostly clear, with a low around 22. Calm wind.
Friday
Sunny, with a high near 34. Calm wind becoming southwest 5 to 10 km/h in the morning.
Friday Night
Mostly clear, with a low around 21. Calm wind.
Saturday
Sunny, with a high near 33. Southwest wind 5 to 13 km/h.
Saturday Night
Mostly clear, with a low around 21. Calm wind.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 32. West southwest wind 5 to 13 km/h.
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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:
1:26 am CDT Sep 14, 2026
Forecast Valid:
4am CDT Sep 14, 2026-6pm CDT Sep 20, 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