Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair and Breezy
56°F
13°C
| Humidity | 27% |
| Wind Speed | W 23 G 36 mph |
| Barometer | 29.59 in (1001.7 mb) |
| Dewpoint | 22°F (-6°C) |
| Visibility | 10.00 mi |
| Last update | 20 Feb 12:52 am CST |
Extended Forecast for
Saint Johns IL
Overnight
Low: 36 °F
Clear
Friday
High: 47 °F
Sunny
Friday Night
Low: 30 °F
Partly Cloudy
then Slight
Chance
Rain/SnowSaturday
High: 43 °F
Mostly Sunny
Saturday Night
Low: 24 °F
Mostly Clear
Sunday
High: 37 °F
Sunny
Sunday Night
Low: 17 °F
Clear
Monday
High: 34 °F
Sunny
Monday Night
Low: 17 °F
Mostly Clear
Detailed Forecast
Overnight
Clear, with a low around 36. West wind 11 to 16 mph, with gusts as high as 28 mph.
Friday
Sunny, with a high near 47. West wind 6 to 16 mph, with gusts as high as 25 mph.
Friday Night
A slight chance of rain showers before 2am, then a slight chance of snow showers between 2am and 4am, then a slight chance of rain showers after 4am. Increasing clouds, with a low around 30. Calm wind becoming north around 5 mph after midnight. Chance of precipitation is 20%.
Saturday
Mostly sunny, with a high near 43. Northwest wind 6 to 10 mph.
Saturday Night
Mostly clear, with a low around 24. Northwest wind around 10 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 37. Northwest wind 10 to 18 mph, with gusts as high as 29 mph.
Sunday Night
Clear, with a low around 17. Northwest wind around 14 mph, with gusts as high as 22 mph.
Monday
Sunny, with a high near 34. North northwest wind 7 to 14 mph, with gusts as high as 21 mph.
Monday Night
Mostly clear, with a low around 17. Northwest wind around 5 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 46. South wind 5 to 14 mph, with gusts as high as 22 mph.
Tuesday Night
Mostly cloudy, with a low around 38. South southwest wind around 14 mph, with gusts as high as 24 mph.
Wednesday
A slight chance of showers. Mostly cloudy, with a high near 57. Southwest wind 9 to 15 mph, with gusts as high as 23 mph.
Wednesday Night
A slight chance of showers. Mostly cloudy, with a low around 34. Southwest wind 6 to 8 mph becoming north northwest after midnight.
Thursday
A slight chance of showers. Mostly sunny, with a high near 54. North northwest wind 6 to 9 mph becoming east in the afternoon.
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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
1:12 am CST Feb 20, 2026
1am CST Feb 20, 2026-6pm CST Feb 26, 2026
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