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Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Overcast

72°F

22°C

Humidity 100%
Wind Speed NE 9 mph
Barometer 30.09 in
Dewpoint 72°F (22°C)
Visibility 7.00 mi
Last update 12 Jul 7:45 am CDT
Extended Forecast for

Simpson IL

  • Today

    Today: A 30 percent chance of showers and thunderstorms, mainly after 3pm. Mostly sunny, with a high near 84. North northeast wind 5 to 8 mph.

    High: 84 °F

    Partly Sunny
    then Chance
    T-storms

  • Tonight

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

    Low: 68 °F

    Chance
    T-storms then
    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 86. Light north northeast wind increasing to 5 to 9 mph in the morning.

    High: 86 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 68. North northeast wind around 6 mph becoming calm in the evening.

    Low: 68 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms after 1pm. Sunny, with a high near 88. Calm wind becoming east northeast 5 to 7 mph in the morning.

    High: 88 °F

    Sunny then
    Slight Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 69. Calm wind.

    Low: 69 °F

    Mostly Clear

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. Light and variable wind.

    High: 89 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 71. Calm wind.

    Low: 71 °F

    Mostly Clear

  • Thursday

    Thursday: A slight chance of showers and thunderstorms after 1pm. Sunny, with a high near 91. Light and variable wind.

    High: 91 °F

    Sunny then
    Slight Chance
    T-storms

Detailed Forecast

Today
A 30 percent chance of showers and thunderstorms, mainly after 3pm. Mostly sunny, with a high near 84. North northeast wind 5 to 8 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Mostly clear, with a low around 68. North northeast wind around 5 mph becoming calm in the evening.
Monday
Sunny, with a high near 86. Light north northeast wind increasing to 5 to 9 mph in the morning.
Monday Night
Mostly clear, with a low around 68. North northeast wind around 6 mph becoming calm in the evening.
Tuesday
A 20 percent chance of showers and thunderstorms after 1pm. Sunny, with a high near 88. Calm wind becoming east northeast 5 to 7 mph in the morning.
Tuesday Night
Mostly clear, with a low around 69. Calm wind.
Wednesday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. Light and variable wind.
Wednesday Night
Mostly clear, with a low around 71. Calm wind.
Thursday
A slight chance of showers and thunderstorms after 1pm. Sunny, with a high near 91. Light and variable wind.
Thursday Night
Mostly clear, with a low around 72. Calm wind.
Friday
A slight chance of showers and thunderstorms. Sunny, with a high near 92. Calm wind becoming west around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 73. Calm wind.
Saturday
Sunny, with a high near 92. Calm wind becoming west 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:
4:31 am CDT Jul 12, 2026
Forecast Valid:
8am CDT Jul 12, 2026-6pm CDT Jul 18, 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