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

73°F

23°C

Humidity 94%
Wind Speed S 6 mph
Barometer 29.95 in
Dewpoint 72°F (22°C)
Visibility 7.00 mi
Last update 14 Jun 8:45 am CDT
Extended Forecast for

Simpson IL

  • Today

    Today: A chance of showers, then showers and thunderstorms likely after 10am. Mostly cloudy, with a high near 82. Southwest wind around 6 mph becoming northwest in the afternoon. Chance of precipitation is 60%.

    High: 82 °F

    T-storms
    Likely

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 7pm. Mostly cloudy, with a low around 68. North northwest wind around 5 mph becoming calm in the evening.

    Low: 68 °F

    Chance
    T-storms then
    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 84. North wind 3 to 5 mph.

    High: 84 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: A 20 percent chance of showers after 1am. Partly cloudy, with a low around 68. Calm wind.

    Low: 68 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Monday

    Monday: A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 85. Light south southwest wind. Chance of precipitation is 40%.

    High: 85 °F

    Chance
    Showers then
    Chance
    T-storms

  • Monday Night

    Monday Night: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70. Calm wind.

    Low: 70 °F

    Chance
    T-storms

  • Tuesday

    Tuesday: A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 86. Calm wind becoming southwest 5 to 7 mph in the morning.

    High: 86 °F

    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 73. South southwest wind 3 to 6 mph.

    Low: 73 °F

    Slight Chance
    T-storms

  • Wednesday

    Wednesday: A chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 89. South southwest wind 6 to 13 mph, with gusts as high as 23 mph.

    High: 89 °F

    Chance
    T-storms

Detailed Forecast

Today
A chance of showers, then showers and thunderstorms likely after 10am. Mostly cloudy, with a high near 82. Southwest wind around 6 mph becoming northwest in the afternoon. Chance of precipitation is 60%.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Mostly cloudy, with a low around 68. North northwest wind around 5 mph becoming calm in the evening.
Sunday
Partly sunny, with a high near 84. North wind 3 to 5 mph.
Sunday Night
A 20 percent chance of showers after 1am. Partly cloudy, with a low around 68. Calm wind.
Monday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 85. Light south southwest wind. Chance of precipitation is 40%.
Monday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70. Calm wind.
Tuesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 86. Calm wind becoming southwest 5 to 7 mph in the morning.
Tuesday Night
A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 73. South southwest wind 3 to 6 mph.
Wednesday
A chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 89. South southwest wind 6 to 13 mph, with gusts as high as 23 mph.
Wednesday Night
Showers likely and possibly a thunderstorm before 1am, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 72. Southwest wind 6 to 8 mph, with gusts as high as 18 mph.
Juneteenth
A chance of showers and thunderstorms. Mostly sunny, with a high near 89. West wind around 6 mph.
Thursday Night
A slight chance of showers and thunderstorms. Mostly clear, with a low around 70. Light and variable wind.
Friday
A slight chance of showers. Mostly sunny, with a high near 89. Calm wind becoming southwest around 6 mph in the afternoon.
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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:
8:32 am CDT Jun 14, 2025
Forecast Valid:
9am CDT Jun 14, 2025-6pm CDT Jun 20, 2025
 
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