National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

79°F

26°C

Humidity 88%
Wind Speed S 6 mph
Barometer 29.92 in (1012.7 mb)
Dewpoint 75°F (24°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 28 Jun 9:52 pm CDT
Extended Forecast for

De Soto IL

Extreme Heat Warning June 29, 11:00am until July 2, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning

  • Tonight

    Tonight: Mostly clear, with a low around 74. South wind 3 to 5 mph.

    Low: 74 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 94. Heat index values as high as 109. South southwest wind 5 to 11 mph.

    High: 94 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 75. South southwest wind 3 to 8 mph.

    Low: 75 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 95. Heat index values as high as 107. South southwest wind 3 to 8 mph.

    High: 95 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 74. South wind around 6 mph becoming calm in the evening.

    Low: 74 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 95. Calm wind becoming south around 6 mph in the afternoon.

    High: 95 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Clear, with a low around 76. South wind around 5 mph becoming calm in the evening.

    Low: 76 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 96. Calm wind becoming south around 6 mph in the afternoon.

    High: 96 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 76. Light and variable wind.

    Low: 76 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly clear, with a low around 74. South wind 3 to 5 mph.
Monday
Sunny, with a high near 94. Heat index values as high as 109. South southwest wind 5 to 11 mph.
Monday Night
Mostly clear, with a low around 75. South southwest wind 3 to 8 mph.
Tuesday
Sunny, with a high near 95. Heat index values as high as 107. South southwest wind 3 to 8 mph.
Tuesday Night
Clear, with a low around 74. South wind around 6 mph becoming calm in the evening.
Wednesday
Sunny, with a high near 95. Calm wind becoming south around 6 mph in the afternoon.
Wednesday Night
Clear, with a low around 76. South wind around 5 mph becoming calm in the evening.
Thursday
Sunny, with a high near 96. Calm wind becoming south around 6 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 76. Light and variable wind.
Friday
A slight chance of showers and thunderstorms after 1pm. Sunny, with a high near 96. Calm wind becoming south around 6 mph in the afternoon.
Friday Night
Mostly clear, with a low around 76. Light and variable wind.
Independence Day
A slight chance of showers and thunderstorms. Sunny, with a high near 96. Light southwest wind.
Saturday Night
Mostly clear, with a low around 75. Calm wind.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 94. Light southwest wind.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
De Soto IL
 37.81°N 89.23°W
Last Update:
9:35 pm CDT Jun 28, 2026
Forecast Valid:
10pm CDT Jun 28, 2026-6pm CDT Jul 5, 2026
 
Forecast Discussion
 
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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