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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

79°F

26°C

Humidity 79%
Wind Speed Calm
Barometer 30.09 in
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 15 Aug 6:52 am CDT
Extended Forecast for

Alto Pass IL

Extreme Heat Warning August 15, 07:11am until August 16, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 15, 07:11am until August 16, 08:00pm

    NOW until 8:00pm Sun

    Extreme Heat Warning

  • Today

    High: 97 °F

    Hot

  • Tonight

    Tonight: Clear, with a low around 76. South southwest wind around 6 mph.

    Low: 76 °F

    Clear

  • Sunday

    Sunday: Increasing clouds and hot, with a high near 98. Heat index values as high as 107. West southwest wind around 6 mph.

    High: 98 °F

    Hot

  • Sunday Night

    Sunday Night: A chance of showers and thunderstorms. Partly cloudy, with a low around 73. Light and variable wind becoming northwest around 5 mph after midnight. Chance of precipitation is 40%.

    Low: 73 °F

    Chance
    T-storms then
    Chance
    Showers

  • Monday

    Monday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88. North wind 5 to 7 mph.

    High: 88 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Monday Night

    Monday Night: Partly cloudy, with a low around 69. Light north wind.

    Low: 69 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 90. Calm wind.

    High: 90 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 72. Calm wind becoming south around 6 mph after midnight.

    Low: 72 °F

    Mostly Clear

Detailed Forecast

Today
Sunny and hot, with a high near 97. Heat index values as high as 105. Southwest wind 3 to 6 mph.
Tonight
Clear, with a low around 76. South southwest wind around 6 mph.
Sunday
Increasing clouds and hot, with a high near 98. Heat index values as high as 107. West southwest wind around 6 mph.
Sunday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 73. Light and variable wind becoming northwest around 5 mph after midnight. Chance of precipitation is 40%.
Monday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88. North wind 5 to 7 mph.
Monday Night
Partly cloudy, with a low around 69. Light north wind.
Tuesday
Sunny, with a high near 90. Calm wind.
Tuesday Night
Mostly clear, with a low around 72. Calm wind becoming south around 6 mph after midnight.
Wednesday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 94. South southwest wind 7 to 10 mph becoming west in the afternoon. Winds could gust as high as 20 mph.
Wednesday Night
A chance of showers and thunderstorms, mainly after 1am. Partly cloudy, with a low around 70. North wind 6 to 8 mph.
Thursday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 85. North northeast wind around 7 mph.
Thursday Night
A slight chance of showers and thunderstorms. Mostly clear, with a low around 66. Northeast wind around 6 mph.
Friday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 83. Northeast wind 5 to 7 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Alto Pass IL
 37.57°N 89.32°W
Last Update:
7:01 am CDT Aug 15, 2026
Forecast Valid:
7am CDT Aug 15, 2026-6pm CDT Aug 21, 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