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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

75°F

24°C

Humidity 78%
Wind Speed SW 8 mph
Barometer 29.96 in
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Last update 27 Jul 7:52 am CDT
Extended Forecast for

2 Miles N Saint Johns IL

Extreme Heat Warning July 27, 08:01am until July 28, 07:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning July 27, 08:01am until July 28, 07:00pm

    NOW until 7:00pm Tue

    Extreme Heat Warning

  • Today

    High: 99 °F

    Hot

  • Tonight

    Tonight: A 20 percent chance of showers and thunderstorms before 8pm. Mostly clear, with a low around 78. South southwest wind 3 to 6 mph.

    Low: 78 °F

    Slight Chance
    T-storms then
    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 93. Heat index values as high as 105. North wind 5 to 9 mph.

    High: 93 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly cloudy during the early evening, then becoming clear, with a low around 69. Northeast wind 3 to 8 mph.

    Low: 69 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 88. Calm wind becoming north northeast 5 to 7 mph in the morning.

    High: 88 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 65. North northeast wind around 5 mph becoming calm in the evening.

    Low: 65 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 89. Light east wind.

    High: 89 °F

    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 68. Calm wind.

    Low: 68 °F

    Partly Cloudy

Detailed Forecast

Today
Sunny and hot, with a high near 99. Heat index values as high as 114. Calm wind becoming southwest around 5 mph in the afternoon.
Tonight
A 20 percent chance of showers and thunderstorms before 8pm. Mostly clear, with a low around 78. South southwest wind 3 to 6 mph.
Tuesday
Mostly sunny, with a high near 93. Heat index values as high as 105. North wind 5 to 9 mph.
Tuesday Night
Mostly cloudy during the early evening, then becoming clear, with a low around 69. Northeast wind 3 to 8 mph.
Wednesday
Sunny, with a high near 88. Calm wind becoming north northeast 5 to 7 mph in the morning.
Wednesday Night
Mostly clear, with a low around 65. North northeast wind around 5 mph becoming calm in the evening.
Thursday
Sunny, with a high near 89. Light east wind.
Thursday Night
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 86. Calm wind becoming south around 5 mph in the afternoon.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. East southeast wind around 6 mph becoming calm in the evening.
Saturday
A chance of showers and thunderstorms. Partly sunny, with a high near 84. North northeast wind 3 to 8 mph.
Saturday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 66. North wind 5 to 7 mph becoming calm in the evening.
Sunday
Mostly sunny, with a high near 86. North 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:
6:46 am CDT Jul 27, 2026
Forecast Valid:
8am CDT Jul 27, 2026-6pm CDT Aug 2, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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