Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Mostly Cloudy
39°F
4°C
| Humidity | 79% |
| Wind Speed | S 7 mph |
| Barometer | 29.82 in (1010.1 mb) |
| Dewpoint | 33°F (1°C) |
| Visibility | 10.00 mi |
| Wind Chill | 34°F (1°C) |
| Last update | 16 Jan 4:52 pm CST |
Extended Forecast for
Saint Johns IL
Tonight
Low: 23 °F
Slight Chance
Rain/Snow
then Slight
Chance Snow
ShowersSaturday
High: 30 °F
Partly Sunny
Saturday Night
Low: 13 °F
Mostly Clear
Sunday
High: 31 °F
Mostly Sunny
Sunday Night
Low: 15 °F
Partly Cloudy
M.L.King Day
High: 24 °F
Sunny
Monday Night
Low: 10 °F
Mostly Clear
Tuesday
High: 35 °F
Sunny
Tuesday Night
Low: 26 °F
Mostly Clear
Detailed Forecast
Tonight
A slight chance of rain and snow showers before 10pm, then a slight chance of snow showers between 10pm and 3am. Mostly cloudy, with a low around 23. West northwest wind 7 to 9 mph. Chance of precipitation is 20%.
Saturday
Partly sunny, with a high near 30. West northwest wind 9 to 14 mph, with gusts as high as 21 mph.
Saturday Night
Mostly clear, with a low around 13. West northwest wind 5 to 10 mph.
Sunday
Mostly sunny, with a high near 31. South southwest wind 5 to 13 mph, with gusts as high as 20 mph.
Sunday Night
Partly cloudy, with a low around 15. South southwest wind 10 to 13 mph becoming northwest after midnight. Winds could gust as high as 21 mph.
M.L.King Day
Sunny, with a high near 24. Northwest wind 7 to 14 mph, with gusts as high as 23 mph.
Monday Night
Mostly clear, with a low around 10. Northwest wind around 5 mph becoming calm.
Tuesday
Sunny, with a high near 35. Southwest wind 6 to 13 mph, with gusts as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 26. South southwest wind around 11 mph, with gusts as high as 21 mph.
Wednesday
Mostly sunny, with a high near 49. Southwest wind 9 to 14 mph, with gusts as high as 21 mph.
Wednesday Night
A slight chance of showers. Partly cloudy, with a low around 26. Southwest wind 6 to 8 mph becoming northwest after midnight.
Thursday
A slight chance of showers. Mostly sunny, with a high near 38. Northwest wind 6 to 9 mph.
Thursday Night
A chance of rain or freezing rain. Partly cloudy, with a low around 25. North wind around 7 mph becoming east southeast after midnight.
Friday
A slight chance of showers. Mostly sunny, with a high near 40. East southeast wind 7 to 9 mph becoming south southwest 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
3:16 pm CST Jan 16, 2026
5pm CST Jan 16, 2026-6pm CST Jan 23, 2026
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