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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

79°F

26°C

Humidity 84%
Wind Speed S 5 mph
Barometer 30.00 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 14 Aug 6:52 am CDT
Extended Forecast for

De Soto IL

Extreme Heat Warning August 14, 08:11am until August 16, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 14, 08:11am until August 16, 08:00pm

    NOW until 8:00pm Sun

    Extreme Heat Warning

  • Today

    High: 98 °F

    Hot

  • Tonight

    Tonight: Mostly clear, with a low around 76. South wind 3 to 5 mph.

    Low: 76 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny and hot, with a high near 99. Heat index values as high as 109. Southwest wind 3 to 6 mph.

    High: 99 °F

    Hot

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 76. South southwest wind 3 to 6 mph.

    Low: 76 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny and hot, with a high near 100. West wind around 6 mph.

    High: 100 °F

    Hot

  • Sunday Night

    Sunday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 74. Light and variable wind.

    Low: 74 °F

    Slight Chance
    T-storms

  • Monday

    Monday: Partly sunny, with a high near 90. North wind 3 to 8 mph.

    High: 90 °F

    Partly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 68. North wind around 6 mph becoming calm in the evening.

    Low: 68 °F

    Partly Cloudy

Detailed Forecast

Today
Mostly sunny and hot, with a high near 98. Heat index values as high as 110. South southwest wind 3 to 6 mph.
Tonight
Mostly clear, with a low around 76. South wind 3 to 5 mph.
Saturday
Sunny and hot, with a high near 99. Heat index values as high as 109. Southwest wind 3 to 6 mph.
Saturday Night
Mostly clear, with a low around 76. South southwest wind 3 to 6 mph.
Sunday
Sunny and hot, with a high near 100. West wind around 6 mph.
Sunday Night
A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 74. Light and variable wind.
Monday
Partly sunny, with a high near 90. North wind 3 to 8 mph.
Monday Night
Partly cloudy, with a low around 68. North wind around 6 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 90. Light and variable wind.
Tuesday Night
Mostly clear, with a low around 70. Light and variable wind.
Wednesday
Mostly sunny, with a high near 96. Light south wind becoming southwest 5 to 10 mph in the morning.
Wednesday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 73. South wind around 6 mph becoming north after midnight.
Thursday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 91. North northwest wind 5 to 9 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
De Soto IL
 37.81°N 89.23°W
Last Update:
7:01 am CDT Aug 14, 2026
Forecast Valid:
8am CDT Aug 14, 2026-6pm CDT Aug 20, 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