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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

N/A

Humidity NA
Wind Speed NA
Barometer NA
Dewpoint N/A
Visibility NA
Last update *** Not a current observation ***
Extended Forecast for

2 Miles N Saint Johns IL

Extreme Heat Warning until July 28, 07:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning until July 28, 07:00pm

    NOW until 7:00pm Tue

    Extreme Heat Warning

  • Overnight

    Low: 77 °F

    Slight Chance
    T-storms

  • Monday

    Monday: Sunny and hot, with a high near 99. Heat index values as high as 115. Calm wind becoming southwest around 5 mph in the afternoon.

    High: 99 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 78. South southwest wind 3 to 6 mph.

    Low: 78 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 93. Heat index values as high as 105. North northwest wind 5 to 10 mph.

    High: 93 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 69. North northeast wind 3 to 8 mph.

    Low: 69 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 88. North wind 3 to 7 mph.

    High: 88 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 66. North northeast wind around 5 mph becoming calm in the evening.

    Low: 66 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 90. Light east northeast wind.

    High: 90 °F

    Sunny

Detailed Forecast

Overnight
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 77. Calm wind.
Monday
Sunny and hot, with a high near 99. Heat index values as high as 115. Calm wind becoming southwest around 5 mph in the afternoon.
Monday Night
Mostly clear, with a low around 78. South southwest wind 3 to 6 mph.
Tuesday
Sunny, with a high near 93. Heat index values as high as 105. North northwest wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 69. North northeast wind 3 to 8 mph.
Wednesday
Sunny, with a high near 88. North wind 3 to 7 mph.
Wednesday Night
Mostly clear, with a low around 66. North northeast wind around 5 mph becoming calm in the evening.
Thursday
Sunny, with a high near 90. Light east northeast wind.
Thursday Night
A slight chance of showers after 1am. Partly cloudy, with a low around 68. Calm wind.
Friday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 88. Calm wind becoming south around 6 mph in the afternoon.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. South wind around 6 mph becoming calm in the evening.
Saturday
A chance of showers and thunderstorms. Mostly sunny, with a high near 84. Light east northeast wind becoming north northeast 5 to 9 mph in the morning.
Saturday Night
Partly cloudy, with a low around 68. North northeast wind 5 to 8 mph becoming calm in the evening.
Sunday
A slight chance of showers and thunderstorms. Sunny, with a high near 86. North northeast wind 3 to 8 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles N Saint Johns IL
 38.06°N 89.24°W
Last Update:
11:46 pm CDT Jul 26, 2026
Forecast Valid:
12am CDT Jul 27, 2026-6pm CDT Aug 2, 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