Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
A Few Clouds
54°F
12°C
| Humidity | 38% |
| Wind Speed | E 7 mph |
| Barometer | 30.18 in (1021.8 mb) |
| Dewpoint | 29°F (-2°C) |
| Visibility | 10.00 mi |
| Wind Chill | 52°F (11°C) |
| Last update | 24 Mar 9:52 pm CDT |
Extended Forecast for
Saint Johns IL
Tonight
Low: 43 °F
Mostly Cloudy
Wednesday
High: 74 °F
Mostly Sunny
Wednesday Night
Low: 61 °F
Mostly Clear
Thursday
High: 85 °F
Sunny
Thursday Night
Low: 44 °F
Slight Chance
Showers then
Showers
LikelyFriday
High: 53 °F
Showers
LikelyFriday Night
Low: 31 °F
Mostly Clear
Saturday
High: 57 °F
Sunny
Saturday Night
Low: 38 °F
Partly Cloudy
Detailed Forecast
Tonight
Mostly cloudy, with a low around 43. East southeast wind 3 to 5 mph.
Wednesday
Mostly sunny, with a high near 74. Light and variable wind becoming south southwest 6 to 11 mph in the morning. Winds could gust as high as 18 mph.
Wednesday Night
Mostly clear, with a low around 61. South wind 9 to 11 mph, with gusts as high as 21 mph.
Thursday
Sunny, with a high near 85. South southwest wind 11 to 16 mph, with gusts as high as 25 mph.
Thursday Night
A slight chance of showers, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 44. South southwest wind 13 to 15 mph becoming north after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 60%.
Friday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 53. North wind around 15 mph, with gusts as high as 23 mph. Chance of precipitation is 60%.
Friday Night
Mostly clear, with a low around 31. North wind 6 to 10 mph, with gusts as high as 18 mph.
Saturday
Sunny, with a high near 57. Light and variable wind becoming east northeast around 6 mph in the morning.
Saturday Night
Partly cloudy, with a low around 38. Southeast wind 3 to 5 mph.
Sunday
Mostly sunny, with a high near 63. South wind 5 to 9 mph.
Sunday Night
Mostly cloudy, with a low around 50. South wind 7 to 9 mph.
Monday
Mostly sunny, with a high near 77. South southwest wind 9 to 13 mph, with gusts as high as 20 mph.
Monday Night
A slight chance of showers. Mostly cloudy, with a low around 58. South wind around 10 mph, with gusts as high as 21 mph.
Tuesday
A chance of showers and thunderstorms. Partly sunny, with a high near 76. South southwest wind 10 to 14 mph, with gusts as high as 22 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
9:21 pm CDT Mar 24, 2026
10pm CDT Mar 24, 2026-6pm CDT Mar 31, 2026
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