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.

Overcast

48°F

9°C

Humidity 76%
Wind Speed S 9 mph
Barometer 30.12 in
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Wind Chill44°F (7°C)
Last update 1 Nov 3:45 pm CDT
Extended Forecast for

Simpson IL

  • This Afternoon

    This Afternoon: A 40 percent chance of showers, mainly before 5pm. Cloudy, with a steady temperature around 45. Light south southwest wind.

    High: 45 °F

    Chance
    Showers

  • Tonight

    Tonight: A 40 percent chance of showers, mainly before 9pm. Patchy frost after 2am. Otherwise, mostly cloudy, with a low around 35. Calm wind.

    Low: 35 °F

    Chance
    Showers then
    Patchy Frost

  • Sunday

    Sunday: Patchy frost before 9am. Otherwise, mostly sunny, with a high near 55. Calm wind becoming north around 5 mph.

    High: 55 °F

    Patchy Frost
    then Mostly
    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 33. Calm wind.

    Low: 33 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 61. Calm wind becoming southwest around 6 mph in the morning.

    High: 61 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 38. Calm wind.

    Low: 38 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 65. Calm wind becoming south 5 to 7 mph in the afternoon.

    High: 65 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 46. South wind 3 to 6 mph.

    Low: 46 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Sunny, with a high near 70. West wind 6 to 9 mph.

    High: 70 °F

    Sunny

Detailed Forecast

This Afternoon
A 40 percent chance of showers, mainly before 5pm. Cloudy, with a steady temperature around 45. Light south southwest wind.
Tonight
A 40 percent chance of showers, mainly before 9pm. Patchy frost after 2am. Otherwise, mostly cloudy, with a low around 35. Calm wind.
Sunday
Patchy frost before 9am. Otherwise, mostly sunny, with a high near 55. Calm wind becoming north around 5 mph.
Sunday Night
Mostly clear, with a low around 33. Calm wind.
Monday
Sunny, with a high near 61. Calm wind becoming southwest around 6 mph in the morning.
Monday Night
Mostly clear, with a low around 38. Calm wind.
Tuesday
Mostly sunny, with a high near 65. Calm wind becoming south 5 to 7 mph in the afternoon.
Tuesday Night
Partly cloudy, with a low around 46. South wind 3 to 6 mph.
Wednesday
Sunny, with a high near 70. West wind 6 to 9 mph.
Wednesday Night
Mostly clear, with a low around 42. Light and variable wind.
Thursday
Sunny, with a high near 67. Calm wind becoming south southeast 5 to 8 mph in the morning.
Thursday Night
A slight chance of showers. Partly cloudy, with a low around 52. South southeast wind around 7 mph.
Friday
A slight chance of showers. Mostly sunny, with a high near 70. Southwest wind 7 to 10 mph, with gusts as high as 18 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
Last Update:
4:07 pm CDT Nov 1, 2025
Forecast Valid:
4pm CDT Nov 1, 2025-6pm CST Nov 7, 2025
 
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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