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.

Mostly Cloudy

84°F

29°C

Humidity 65%
Wind Speed S 14 mph
Barometer 29.85 in (1010.5 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Heat Index89°F (32°C)
Last update 21 Jun 11:52 am CDT
Extended Forecast for

Grand Tower IL

  • This Afternoon

    This Afternoon: A 40 percent chance of showers and thunderstorms, mainly between 1pm and 5pm. Mostly cloudy, with a high near 89. South wind 9 to 15 mph, with gusts as high as 25 mph.

    High: 89 °F

    Chance
    T-storms

  • Tonight

    Tonight: Showers and thunderstorms before 1am, then showers likely and possibly a thunderstorm between 1am and 4am, then a chance of showers and thunderstorms after 4am. Low around 69. South wind 7 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 90%.

    Low: 69 °F

    T-storms

  • Monday

    Monday: A 30 percent chance of showers and thunderstorms, mainly before 11am. Cloudy, then gradually becoming mostly sunny, with a high near 80. North northwest wind 7 to 9 mph.

    High: 80 °F

    Chance
    T-storms then
    Partly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 62. North wind 5 to 8 mph becoming calm in the evening.

    Low: 62 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 84. Light northeast wind.

    High: 84 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after 1am. Mostly clear, with a low around 63. Light north wind.

    Low: 63 °F

    Mostly Clear
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Light south wind.

    High: 86 °F

    Mostly Sunny
    then Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A slight chance of showers and thunderstorms. Partly cloudy, with a low around 66. Light south wind.

    Low: 66 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: A chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Light southwest wind.

    High: 86 °F

    Mostly Sunny
    then Chance
    T-storms

Detailed Forecast

This Afternoon
A 40 percent chance of showers and thunderstorms, mainly between 1pm and 5pm. Mostly cloudy, with a high near 89. South wind 9 to 15 mph, with gusts as high as 25 mph.
Tonight
Showers and thunderstorms before 1am, then showers likely and possibly a thunderstorm between 1am and 4am, then a chance of showers and thunderstorms after 4am. Low around 69. South wind 7 to 15 mph, with gusts as high as 24 mph. Chance of precipitation is 90%.
Monday
A 30 percent chance of showers and thunderstorms, mainly before 11am. Cloudy, then gradually becoming mostly sunny, with a high near 80. North northwest wind 7 to 9 mph.
Monday Night
Partly cloudy, with a low around 62. North wind 5 to 8 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 84. Light northeast wind.
Tuesday Night
A 20 percent chance of showers after 1am. Mostly clear, with a low around 63. Light north wind.
Wednesday
A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Light south wind.
Wednesday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 66. Light south wind.
Thursday
A chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Light southwest wind.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 66. Calm wind.
Friday
A chance of showers and thunderstorms. Mostly sunny, with a high near 87. Light south southeast wind.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 70. South wind around 5 mph becoming calm in the evening.
Saturday
A chance of showers and thunderstorms. Partly sunny, with a high near 88. South southwest wind 5 to 9 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Grand Tower IL
 37.62°N 89.49°W
Last Update:
11:01 am CDT Jun 21, 2026
Forecast Valid:
12pm CDT Jun 21, 2026-6pm CDT Jun 27, 2026
 
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Additional Resources

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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