Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Mostly Cloudy
36°F
2°C
| Humidity | 64% |
| Wind Speed | N 5 mph |
| Barometer | 30.04 in (1017.3 mb) |
| Dewpoint | 25°F (-4°C) |
| Visibility | 10.00 mi |
| Wind Chill | 32°F (0°C) |
| Last update | 20 Feb 11:52 pm CST |
Extended Forecast for
Saint Johns IL
Overnight
Low: 30 °F
Mostly Cloudy
Saturday
High: 43 °F
Chance
Sprinkles/Flurries
then Partly
SunnySaturday Night
Low: 23 °F
Mostly Clear
Sunday
High: 36 °F
Sunny
Sunday Night
Low: 17 °F
Mostly Clear
Monday
High: 33 °F
Sunny
Monday Night
Low: 17 °F
Mostly Clear
Tuesday
High: 48 °F
Partly Sunny
Tuesday Night
Low: 39 °F
Mostly Cloudy
Detailed Forecast
Overnight
Mostly cloudy, with a low around 30. North wind 3 to 6 mph.
Saturday
A chance of sprinkles and flurries before 11am, then a chance of sprinkles between 11am and noon. Mostly cloudy, with a high near 43. Northwest wind 6 to 9 mph.
Saturday Night
Mostly clear, with a low around 23. Northwest wind 7 to 11 mph, with gusts as high as 21 mph.
Sunday
Sunny, with a high near 36. Northwest wind 11 to 18 mph, with gusts as high as 28 mph.
Sunday Night
Mostly clear, with a low around 17. Northwest wind around 14 mph, with gusts as high as 23 mph.
Monday
Sunny, with a high near 33. North northwest wind 7 to 14 mph, with gusts as high as 22 mph.
Monday Night
Mostly clear, with a low around 17. Northwest wind around 5 mph becoming calm in the evening.
Tuesday
Partly sunny, with a high near 48. South southwest wind 5 to 15 mph, with gusts as high as 24 mph.
Tuesday Night
Mostly cloudy, with a low around 39. South southwest wind around 14 mph, with gusts as high as 23 mph.
Wednesday
Mostly cloudy, with a high near 60. South southwest wind 11 to 14 mph, with gusts as high as 22 mph.
Wednesday Night
A chance of showers. Mostly cloudy, with a low around 37. South southwest wind 8 to 10 mph becoming north northwest after midnight.
Thursday
A slight chance of showers. Partly sunny, with a high near 53. North northwest wind 6 to 9 mph.
Thursday Night
A slight chance of showers. Mostly clear, with a low around 32. North northwest wind around 6 mph becoming south southwest after midnight.
Friday
Sunny, with a high near 58. South southwest wind 6 to 10 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
9:16 pm CST Feb 20, 2026
12am CST Feb 21, 2026-6pm CST Feb 27, 2026
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