National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

A Few Clouds

37°F

3°C

Humidity 48%
Wind Speed W 12 mph
Barometer 30.54 in
Dewpoint 19°F (-7°C)
Visibility 10.00 mi
Wind Chill29°F (-2°C)
Last update 11 Jan 3:45 pm CST
Extended Forecast for

4 Miles SW Simpson IL

  • This Afternoon

    This Afternoon: Sunny, with a steady temperature around 36. Calm wind.

    High: 36 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 23. Light and variable wind.

    Low: 23 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 48. Southwest wind 5 to 10 mph, with gusts as high as 18 mph.

    High: 48 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 33. South southwest wind around 6 mph.

    Low: 33 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 56. Southwest wind 6 to 13 mph, with gusts as high as 22 mph.

    High: 56 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers, mainly after midnight. Mostly cloudy, with a low around 41. West southwest wind 5 to 8 mph, with gusts as high as 18 mph.

    Low: 41 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A 30 percent chance of showers, mainly before noon. Mostly cloudy, with a high near 46. Northwest wind 6 to 15 mph, with gusts as high as 26 mph.

    High: 46 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 19. North northwest wind 10 to 14 mph, with gusts as high as 25 mph.

    Low: 19 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 33. North northwest wind 5 to 10 mph becoming light west in the afternoon. Winds could gust as high as 20 mph.

    High: 33 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a steady temperature around 36. Calm wind.
Tonight
Clear, with a low around 23. Light and variable wind.
Monday
Sunny, with a high near 48. Southwest wind 5 to 10 mph, with gusts as high as 18 mph.
Monday Night
Mostly clear, with a low around 33. South southwest wind around 6 mph.
Tuesday
Mostly sunny, with a high near 56. Southwest wind 6 to 13 mph, with gusts as high as 22 mph.
Tuesday Night
A 30 percent chance of showers, mainly after midnight. Mostly cloudy, with a low around 41. West southwest wind 5 to 8 mph, with gusts as high as 18 mph.
Wednesday
A 30 percent chance of showers, mainly before noon. Mostly cloudy, with a high near 46. Northwest wind 6 to 15 mph, with gusts as high as 26 mph.
Wednesday Night
Mostly cloudy, with a low around 19. North northwest wind 10 to 14 mph, with gusts as high as 25 mph.
Thursday
Mostly sunny, with a high near 33. North northwest wind 5 to 10 mph becoming light west in the afternoon. Winds could gust as high as 20 mph.
Thursday Night
Mostly cloudy, with a low around 24. Calm wind becoming south southwest around 6 mph after midnight.
Friday
Partly sunny, with a high near 43. West southwest wind 6 to 10 mph, with gusts as high as 20 mph.
Friday Night
Mostly cloudy, with a low around 25. West wind 3 to 6 mph.
Saturday
Partly sunny, with a high near 35. West northwest wind 6 to 10 mph, with gusts as high as 18 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SW Simpson IL
 37.44°N 88.82°W
Last Update:
3:17 pm CST Jan 11, 2026
Forecast Valid:
4pm CST Jan 11, 2026-6pm CST Jan 17, 2026
 
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Additional Resources

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Chance of Precipitation