Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair
25°F
-4°C
| Humidity | 60% |
| Wind Speed | NW 8 mph |
| Barometer | 30.10 in (1019.7 mb) |
| Dewpoint | 13°F (-11°C) |
| Visibility | 10.00 mi |
| Wind Chill | 16°F (-9°C) |
| Last update | 14 Jan 11:52 pm CST |
Extended Forecast for
Saint Johns IL
Overnight
Low: 19 °F
Clear
Thursday
High: 33 °F
Sunny
Thursday Night
Low: 29 °F⇑
Slight Chance
SnowFriday
High: 45 °F
Partly Sunny
Friday Night
Low: 22 °F
Mostly Cloudy
Saturday
High: 28 °F
Partly Sunny
Saturday Night
Low: 10 °F
Partly Cloudy
Sunday
High: 24 °F
Sunny
Sunday Night
Low: 15 °F
Partly Cloudy
Detailed Forecast
Overnight
Clear, with a low around 19. Northwest wind around 9 mph, with gusts as high as 18 mph.
Thursday
Sunny, with a high near 33. Northwest wind 5 to 9 mph becoming south southwest in the afternoon.
Thursday Night
A slight chance of snow between 9pm and 3am. Mostly cloudy, with a temperature rising to around 34 by 3am. Light south wind becoming southwest 8 to 13 mph in the evening. Winds could gust as high as 21 mph. Chance of precipitation is 20%.
Friday
Partly sunny, with a high near 45. West wind 11 to 14 mph, with gusts as high as 21 mph.
Friday Night
Mostly cloudy, with a low around 22. West wind around 11 mph, with gusts as high as 20 mph.
Saturday
Partly sunny, with a high near 28. West northwest wind 10 to 15 mph, with gusts as high as 23 mph.
Saturday Night
Partly cloudy, with a low around 10. Northwest wind 7 to 9 mph.
Sunday
Sunny, with a high near 24. West northwest wind 7 to 11 mph becoming southwest in the afternoon.
Sunday Night
Partly cloudy, with a low around 15. West southwest wind 7 to 10 mph, with gusts as high as 20 mph.
M.L.King Day
Mostly sunny, with a high near 29. Northwest wind 9 to 14 mph, with gusts as high as 21 mph.
Monday Night
Mostly clear, with a low around 10. Northwest wind 5 to 8 mph.
Tuesday
Sunny, with a high near 32. West wind 5 to 10 mph becoming south southwest in the afternoon.
Tuesday Night
Mostly clear, with a low around 20. South southwest wind around 9 mph.
Wednesday
Sunny, with a high near 40. Southwest wind 9 to 11 mph, with gusts as high as 18 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
10:26 pm CST Jan 14, 2026
12am CST Jan 15, 2026-6pm CST Jan 21, 2026
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