Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Overcast
29°F
-2°C
| Humidity | 78% |
| Wind Speed | N 13 mph |
| Barometer | 30.29 in (1026.1 mb) |
| Dewpoint | 23°F (-5°C) |
| Visibility | 10.00 mi |
| Wind Chill | 19°F (-7°C) |
| Last update | 8 Dec 4:52 am CST |
Extended Forecast for
Saint Johns IL
Today
High: 36 °F
Mostly Sunny
Tonight
Low: 25 °F
Increasing
CloudsTuesday
High: 50 °F
Mostly Sunny
Tuesday Night
Low: 42 °F
Increasing
CloudsWednesday
High: 50 °F
Partly Sunny
Wednesday Night
Low: 27 °F
Mostly Cloudy
Thursday
High: 39 °F
Slight Chance
Snow Showers
then Mostly
CloudyThursday Night
Low: 24 °F
Mostly Cloudy
Friday
High: 35 °F
Partly Sunny
Detailed Forecast
Today
Mostly sunny, with a high near 36. North wind 5 to 7 mph becoming calm in the afternoon.
Tonight
Increasing clouds, with a low around 25. Light and variable wind becoming south southwest 5 to 10 mph after midnight. Winds could gust as high as 18 mph.
Tuesday
Mostly sunny, with a high near 50. South southwest wind 11 to 15 mph, with gusts as high as 21 mph.
Tuesday Night
Increasing clouds, with a low around 42. Southwest wind 14 to 17 mph, with gusts as high as 25 mph.
Wednesday
Partly sunny, with a high near 50. West southwest wind 10 to 17 mph becoming northwest in the afternoon. Winds could gust as high as 25 mph.
Wednesday Night
Mostly cloudy, with a low around 27. Northwest wind 3 to 8 mph.
Thursday
A 20 percent chance of snow showers before noon. Mostly cloudy, with a high near 39. Light and variable wind becoming south southwest 5 to 8 mph in the morning.
Thursday Night
Mostly cloudy, with a low around 24. South wind 6 to 8 mph becoming north northwest after midnight.
Friday
Partly sunny, with a high near 35. Northwest wind 8 to 13 mph.
Friday Night
Mostly cloudy, with a low around 11. North northwest wind around 10 mph.
Saturday
Mostly sunny, with a high near 22. North northwest wind 5 to 10 mph.
Saturday Night
Mostly cloudy, with a low around 11. North northeast wind 3 to 6 mph.
Sunday
Mostly sunny, with a high near 28. North northwest wind 6 to 8 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
5:01 am CST Dec 8, 2025
5am CST Dec 8, 2025-6pm CST Dec 14, 2025
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