Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
A Few Clouds
84°F
29°C
| Humidity | 45% |
| Wind Speed | N 12 mph |
| Barometer | 30.00 in |
| Dewpoint | 61°F (16°C) |
| Visibility | 10.00 mi |
| Heat Index | 84°F (29°C) |
| Last update | 27 Aug 3:52 pm CDT |
Extended Forecast for
Saint Johns IL
This Afternoon
High: 85 °F
Sunny
Tonight
Low: 64 °F
Mostly Clear
Friday
High: 88 °F
Sunny
Friday Night
Low: 63 °F
Mostly Clear
Saturday
High: 90 °F
Sunny
Saturday Night
Low: 66 °F
Mostly Clear
Sunday
High: 95 °F
Sunny
Sunday Night
Low: 71 °F
Mostly Clear
Monday
High: 97 °F
Hot
Detailed Forecast
This Afternoon
Sunny, with a steady temperature around 85. North northwest wind around 8 mph.
Tonight
Mostly clear, with a low around 64. Light north northeast wind.
Friday
Sunny, with a high near 88. Calm wind becoming north northeast around 6 mph in the afternoon.
Friday Night
Mostly clear, with a low around 63. Calm wind.
Saturday
Sunny, with a high near 90. Light and variable wind.
Saturday Night
Mostly clear, with a low around 66. Calm wind.
Sunday
Sunny, with a high near 95. Light south wind becoming south southwest 5 to 10 mph in the morning.
Sunday Night
Mostly clear, with a low around 71. South wind 3 to 6 mph.
Monday
Sunny and hot, with a high near 97. South southwest wind 5 to 10 mph.
Monday Night
Mostly clear, with a low around 74. South wind 3 to 7 mph.
Tuesday
Sunny and hot, with a high near 98. Southwest wind 3 to 8 mph.
Tuesday Night
Mostly clear, with a low around 75. South southwest wind 3 to 5 mph.
Wednesday
Sunny and hot, with a high near 98. Southwest wind 3 to 8 mph.
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Saint Johns IL
38.03°N 89.24°W
38.03°N 89.24°W
4:16 pm CDT Aug 27, 2026
4pm CDT Aug 27, 2026-6pm CDT Sep 2, 2026
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