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

22°F

-6°C

Humidity 71%
Wind Speed S 8 mph
Barometer 30.20 in
Dewpoint 14°F (-10°C)
Visibility 10.00 mi
Wind Chill13°F (-11°C)
Last update 24 Feb 6:15 am CST
Extended Forecast for

Simpson IL

  • Today

    Today: Partly sunny, with a high near 49. Light and variable wind becoming south southwest 12 to 17 mph in the morning. Winds could gust as high as 33 mph.

    High: 49 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 40. South southwest wind 9 to 14 mph becoming light southwest after midnight. Winds could gust as high as 29 mph.

    Low: 40 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 57. Light and variable wind.

    High: 57 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A 50 percent chance of showers, mainly after midnight. Mostly cloudy, with a low around 41. Calm wind becoming northeast around 5 mph after midnight.

    Low: 41 °F

    Slight Chance
    Showers then
    Chance
    Showers

  • Thursday

    Thursday: A 40 percent chance of showers, mainly before noon. Mostly cloudy, with a high near 55. North wind 5 to 7 mph.

    High: 55 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 32. Light and variable wind.

    Low: 32 °F

    Partly Cloudy

  • Friday

    Friday: Sunny, with a high near 60. Calm wind becoming south southwest around 5 mph.

    High: 60 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 40. Calm wind.

    Low: 40 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 67. Calm wind becoming south southwest 5 to 7 mph in the morning.

    High: 67 °F

    Sunny

Detailed Forecast

Today
Partly sunny, with a high near 49. Light and variable wind becoming south southwest 12 to 17 mph in the morning. Winds could gust as high as 33 mph.
Tonight
Mostly cloudy, with a low around 40. South southwest wind 9 to 14 mph becoming light southwest after midnight. Winds could gust as high as 29 mph.
Wednesday
Mostly cloudy, with a high near 57. Light and variable wind.
Wednesday Night
A 50 percent chance of showers, mainly after midnight. Mostly cloudy, with a low around 41. Calm wind becoming northeast around 5 mph after midnight.
Thursday
A 40 percent chance of showers, mainly before noon. Mostly cloudy, with a high near 55. North wind 5 to 7 mph.
Thursday Night
Partly cloudy, with a low around 32. Light and variable wind.
Friday
Sunny, with a high near 60. Calm wind becoming south southwest around 5 mph.
Friday Night
Mostly clear, with a low around 40. Calm wind.
Saturday
Sunny, with a high near 67. Calm wind becoming south southwest 5 to 7 mph in the morning.
Saturday Night
Mostly clear, with a low around 36. Light and variable wind becoming north around 6 mph in the evening.
Sunday
A slight chance of showers. Partly sunny, with a high near 52. Northeast wind 6 to 8 mph.
Sunday Night
A chance of showers. Mostly cloudy, with a low around 36. Northeast wind around 6 mph.
Monday
A chance of showers. Mostly cloudy, with a high near 56. East northeast wind 6 to 8 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
Last Update:
5:26 am CST Feb 24, 2026
Forecast Valid:
6am CST Feb 24, 2026-6pm CST Mar 2, 2026
 
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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