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.

A Few Clouds

94°F

34°C

Humidity 49%
Wind Speed Calm
Barometer 30.04 in (1016.7 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index102°F (39°C)
Last update 18 Aug 1:52 pm CDT
Extended Forecast for

2 Miles NW Grand Tower IL

Heat Advisory August 18, 02:54pm until August 19, 07:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 18, 02:54pm until August 19, 07:00pm

    NOW until 7:00pm Tue

    Heat Advisory

  • This Afternoon

    High: 97 °F

    Slight Chance
    T-storms

  • Tonight

    Tonight: Clear, with a low around 75. Calm wind.

    Low: 75 °F

    Clear

  • Tuesday

    Tuesday: A 50 percent chance of showers and thunderstorms, mainly after 4pm. Sunny and hot, with a high near 98. Heat index values as high as 109. Light and variable wind.

    High: 98 °F

    Sunny then
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72. Calm wind.

    Low: 72 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 90. North wind 3 to 8 mph.

    High: 90 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 68. North northeast wind 5 to 7 mph.

    Low: 68 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 89. North northeast wind 6 to 8 mph.

    High: 89 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 68. North northeast wind around 6 mph becoming calm in the evening.

    Low: 68 °F

    Mostly Clear

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms after 4pm. Sunny and hot, with a high near 97. Heat index values as high as 105. Light south southeast wind.
Tonight
Clear, with a low around 75. Calm wind.
Tuesday
A 50 percent chance of showers and thunderstorms, mainly after 4pm. Sunny and hot, with a high near 98. Heat index values as high as 109. Light and variable wind.
Tuesday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72. Calm wind.
Wednesday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 90. North wind 3 to 8 mph.
Wednesday Night
Partly cloudy, with a low around 68. North northeast wind 5 to 7 mph.
Thursday
Mostly sunny, with a high near 89. North northeast wind 6 to 8 mph.
Thursday Night
Mostly clear, with a low around 68. North northeast wind around 6 mph becoming calm in the evening.
Friday
Sunny, with a high near 91. Calm wind becoming north around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 67. Light north wind.
Saturday
Sunny, with a high near 91. Calm wind becoming north northwest around 6 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 64. North wind 3 to 6 mph.
Sunday
Sunny, with a high near 84. North wind 3 to 7 mph.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles NW Grand Tower IL
 37.67°N 89.54°W
Last Update:
2:30 pm CDT Aug 18, 2025
Forecast Valid:
2pm CDT Aug 18, 2025-6pm CDT Aug 24, 2025
 
Forecast Discussion
 
Get as KML Get as XML

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