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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

39°F

4°C

Humidity 71%
Wind Speed Calm
Barometer 30.10 in
Dewpoint 30°F (-1°C)
Visibility 10.00 mi
Last update 14 Mar 3:15 am CDT
Extended Forecast for

Simpson IL

  • Overnight

    Overnight: Mostly clear, with a steady temperature around 43. Calm wind.

    Low: 43 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 69. Light and variable wind becoming southeast 5 to 8 mph in the morning.

    High: 69 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 55. South southeast wind 5 to 10 mph, with gusts as high as 24 mph.

    Low: 55 °F

    Mostly Clear

  • Sunday

    Sunday: A chance of showers between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Increasing clouds, with a high near 73. Breezy, with a south wind 14 to 23 mph, with gusts as high as 40 mph. Chance of precipitation is 50%.

    High: 73 °F

    Breezy.
    Mostly Cloudy
    then Chance
    Showers

  • Sunday Night

    Sunday Night: Rain showers before 1am, then a chance of rain and snow showers between 1am and 4am, then a chance of snow showers after 4am. Some thunder is also possible. Low around 27. South wind 14 to 18 mph becoming west northwest after midnight. Winds could gust as high as 37 mph. Chance of precipitation is 100%.

    Low: 27 °F

    Showers then
    Rain/Snow

  • Monday

    Monday: Mostly cloudy, with a high near 34. West northwest wind around 16 mph, with gusts as high as 31 mph.

    High: 34 °F

    Mostly Cloudy

  • Monday Night

    Monday Night: Partly cloudy, with a low around 16. West northwest wind 5 to 11 mph, with gusts as high as 23 mph.

    Low: 16 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 39. West northwest wind 3 to 6 mph.

    High: 39 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 28. Calm wind becoming south 5 to 8 mph after midnight. Winds could gust as high as 21 mph.

    Low: 28 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Mostly clear, with a steady temperature around 43. Calm wind.
Saturday
Sunny, with a high near 69. Light and variable wind becoming southeast 5 to 8 mph in the morning.
Saturday Night
Mostly clear, with a low around 55. South southeast wind 5 to 10 mph, with gusts as high as 24 mph.
Sunday
A chance of showers between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Increasing clouds, with a high near 73. Breezy, with a south wind 14 to 23 mph, with gusts as high as 40 mph. Chance of precipitation is 50%.
Sunday Night
Rain showers before 1am, then a chance of rain and snow showers between 1am and 4am, then a chance of snow showers after 4am. Some thunder is also possible. Low around 27. South wind 14 to 18 mph becoming west northwest after midnight. Winds could gust as high as 37 mph. Chance of precipitation is 100%.
Monday
Mostly cloudy, with a high near 34. West northwest wind around 16 mph, with gusts as high as 31 mph.
Monday Night
Partly cloudy, with a low around 16. West northwest wind 5 to 11 mph, with gusts as high as 23 mph.
Tuesday
Sunny, with a high near 39. West northwest wind 3 to 6 mph.
Tuesday Night
Mostly cloudy, with a low around 28. Calm wind becoming south 5 to 8 mph after midnight. Winds could gust as high as 21 mph.
Wednesday
Mostly cloudy, with a high near 58. South wind 10 to 14 mph, with gusts as high as 25 mph.
Wednesday Night
Mostly clear, with a low around 41. South southwest wind around 6 mph becoming calm after midnight.
Thursday
Sunny, with a high near 71. Calm wind becoming southwest around 5 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 47. Calm wind.
Friday
Sunny, with a high near 72. Light and variable wind becoming west 5 to 7 mph in the morning.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
Last Update:
1:26 am CDT Mar 14, 2026
Forecast Valid:
3am CDT Mar 14, 2026-6pm CDT Mar 20, 2026
 
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Additional Resources

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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