Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Partly Cloudy

74°F

23°C

Humidity 95%
Wind Speed Calm
Barometer 30.11 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Last update 16 Aug 1:35 am CDT
Extended Forecast for

Simpson IL

Heat Advisory August 16, 12:00pm until August 19, 07:00pm
Click here for hazard details and duration
Heat Advisory
  • Overnight

    Overnight: Clear, with a low around 73. Calm wind.

    Low: 73 °F

    Clear

  • Saturday

    Saturday: Sunny and hot, with a high near 97. Heat index values as high as 105. Calm wind.

    High: 97 °F

    Hot

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 74. Calm wind.

    Low: 74 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny and hot, with a high near 99. Heat index values as high as 105. Calm wind.

    High: 99 °F

    Hot

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 75. Calm wind.

    Low: 75 °F

    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 100. Calm wind.

    High: 100 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 76. Calm wind.

    Low: 76 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 101. Light west southwest wind.

    High: 101 °F

    Hot

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms.  Mostly clear, with a low around 73. Calm wind.

    Low: 73 °F

    Chance
    Showers

Detailed Forecast

Overnight
Clear, with a low around 73. Calm wind.
Saturday
Sunny and hot, with a high near 97. Heat index values as high as 105. Calm wind.
Saturday Night
Mostly clear, with a low around 74. Calm wind.
Sunday
Sunny and hot, with a high near 99. Heat index values as high as 105. Calm wind.
Sunday Night
Mostly clear, with a low around 75. Calm wind.
Monday
Sunny and hot, with a high near 100. Calm wind.
Monday Night
Mostly clear, with a low around 76. Calm wind.
Tuesday
Sunny and hot, with a high near 101. Light west southwest wind.
Tuesday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 73. Calm wind.
Wednesday
A chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 91. Calm wind becoming north around 6 mph in the morning.
Wednesday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 68. North wind around 5 mph becoming calm in the evening.
Thursday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 88. Calm wind becoming north northeast around 6 mph in the morning.
Thursday Night
Mostly clear, with a low around 66. North northeast wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 90. Calm wind becoming north northeast around 5 mph in the afternoon.
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ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
11:15 pm CDT Aug 15, 2025
1am CDT Aug 16, 2025-6pm CDT Aug 22, 2025
 
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Additional Resources

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Hourly Weather Forecast

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