Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair
82°F
28°C
| Humidity | 48% |
| Wind Speed | W 8 mph |
| Barometer | 30.08 in |
| Dewpoint | 61°F (16°C) |
| Visibility | 10.00 mi |
| Heat Index | 82°F (28°C) |
| Last update | 24 Aug 12:52 pm CDT |
Extended Forecast for
Saint Johns IL
This Afternoon
High: 83 °F
Mostly Sunny
Tonight
Low: 61 °F
Partly Cloudy
Tuesday
High: 88 °F
Mostly Sunny
Tuesday Night
Low: 67 °F
Partly Cloudy
Wednesday
High: 91 °F
Mostly Sunny
Wednesday Night
Low: 68 °F
Slight Chance
T-stormsThursday
High: 89 °F
Sunny
Thursday Night
Low: 65 °F
Mostly Clear
Friday
High: 89 °F
Sunny
Detailed Forecast
This Afternoon
Mostly sunny, with a high near 83. Light and variable wind.
Tonight
Partly cloudy, with a low around 61. Calm wind.
Tuesday
Mostly sunny, with a high near 88. Light east wind.
Tuesday Night
Partly cloudy, with a low around 67. Calm wind.
Wednesday
Mostly sunny, with a high near 91. Light and variable wind.
Wednesday Night
A slight chance of showers and thunderstorms. Mostly clear, with a low around 68. Calm wind. Chance of precipitation is 20%.
Thursday
Sunny, with a high near 89. Calm wind becoming north northwest 5 to 8 mph in the morning.
Thursday Night
Mostly clear, with a low around 65. North wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 89. Calm wind becoming north around 6 mph in the afternoon.
Friday Night
Mostly clear, with a low around 65. Light and variable wind.
Saturday
Sunny, with a high near 91. Light southeast wind.
Saturday Night
Mostly clear, with a low around 68. Calm wind.
Sunday
Sunny, with a high near 95. Calm wind becoming south southwest 5 to 8 mph in the morning.
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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
12:21 pm CDT Aug 24, 2026
1pm CDT Aug 24, 2026-6pm CDT Aug 30, 2026
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