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

81°F

27°C

Humidity 70%
Wind Speed NA
Barometer 29.94 in
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 19 Aug 2:52 pm CDT
Extended Forecast for

Grand Tower IL

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 83. South wind around 5 mph.

    High: 83 °F

    Mostly Sunny

  • Tonight

    Tonight: Showers and thunderstorms likely, mainly before 1am. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 68. Light and variable wind. Chance of precipitation is 70%.

    Low: 68 °F

    Heavy Rain
    then Chance
    T-storms

  • Thursday

    Thursday: A 30 percent chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 85. Calm wind becoming north around 5 mph in the afternoon.

    High: 85 °F

    Partly Sunny
    then Chance
    Showers

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 66. Light north wind.

    Low: 66 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 87. Calm wind.

    High: 87 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 66. Calm wind.

    Low: 66 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 87. Calm wind becoming northwest around 6 mph in the afternoon.

    High: 87 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 65. Light north northeast wind.

    Low: 65 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 86. Calm wind becoming north around 5 mph in the afternoon.

    High: 86 °F

    Sunny

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 83. South wind around 5 mph.
Tonight
Showers and thunderstorms likely, mainly before 1am. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 68. Light and variable wind. Chance of precipitation is 70%.
Thursday
A 30 percent chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 85. Calm wind becoming north around 5 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 66. Light north wind.
Friday
Mostly sunny, with a high near 87. Calm wind.
Friday Night
Mostly clear, with a low around 66. Calm wind.
Saturday
Mostly sunny, with a high near 87. Calm wind becoming northwest around 6 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 65. Light north northeast wind.
Sunday
Sunny, with a high near 86. Calm wind becoming north around 5 mph in the afternoon.
Sunday Night
A slight chance of showers. Partly cloudy, with a low around 64. Light east wind.
Monday
A slight chance of showers. Mostly sunny, with a high near 86. Calm wind becoming south southeast around 5 mph in the afternoon.
Monday Night
A slight chance of showers and thunderstorms. Mostly clear, with a low around 66. East southeast wind 3 to 5 mph.
Tuesday
Mostly sunny, with a high near 88. East wind 3 to 6 mph.
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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 Aug 19, 2026
Forecast Valid:
3pm CDT Aug 19, 2026-6pm CDT Aug 25, 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