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.

Partly Cloudy

97°F

36°C

Humidity 37%
Wind Speed SE 7 mph
Barometer 30.02 in
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Heat Index101°F (38°C)
Last update 1 Sep 2:48 pm CDT
Extended Forecast for

Grand Tower IL

Extreme Heat Warning until September 5, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning until September 5, 08:00pm

    NOW until 8:00pm Sat

    Extreme Heat Warning

  • This Afternoon

    High: 98 °F

    Hot

  • Tonight

    Tonight: Clear, with a low around 75. Light south wind.

    Low: 75 °F

    Clear

  • Wednesday

    Wednesday: Sunny and hot, with a high near 98. Heat index values as high as 107. Calm wind becoming south southwest around 6 mph in the afternoon.

    High: 98 °F

    Hot

  • Wednesday Night

    Wednesday Night: Clear, with a low around 75. Light south wind.

    Low: 75 °F

    Clear

  • Thursday

    Thursday: Sunny and hot, with a high near 98. Calm wind becoming south southwest around 6 mph in the afternoon.

    High: 98 °F

    Hot

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 75. Light south wind.

    Low: 75 °F

    Mostly Clear

  • Friday

    Friday: Sunny and hot, with a high near 98. Light south southwest wind.

    High: 98 °F

    Hot

  • Friday Night

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

    Low: 74 °F

    Mostly Clear

Detailed Forecast

This Afternoon
Sunny and hot, with a high near 98. Heat index values as high as 106. Light south southwest wind.
Tonight
Clear, with a low around 75. Light south wind.
Wednesday
Sunny and hot, with a high near 98. Heat index values as high as 107. Calm wind becoming south southwest around 6 mph in the afternoon.
Wednesday Night
Clear, with a low around 75. Light south wind.
Thursday
Sunny and hot, with a high near 98. Calm wind becoming south southwest around 6 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 75. Light south wind.
Friday
Sunny and hot, with a high near 98. Light south southwest wind.
Friday Night
Mostly clear, with a low around 74. Calm wind.
Saturday
A slight chance of showers and thunderstorms. Sunny and hot, with a high near 97. Calm wind.
Saturday Night
A slight chance of showers and thunderstorms before 1am. Mostly clear, with a low around 72. Calm wind.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 95. Calm wind becoming north around 5 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 70. Calm wind.
Labor Day
Sunny, with a high near 92. Calm wind becoming east around 5 mph in the afternoon.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Grand Tower IL
 37.64°N 89.52°W
Last Update:
1:26 pm CDT Sep 1, 2026
Forecast Valid:
3pm CDT Sep 1, 2026-6pm CDT Sep 7, 2026
 
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