Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Overcast
29°F
-2°C
| Humidity | 45% |
| Wind Speed | SW 8 G 20 mph |
| Barometer | 30.06 in (1018.5 mb) |
| Dewpoint | 10°F (-12°C) |
| Visibility | 10.00 mi |
| Wind Chill | 21°F (-6°C) |
| Last update | 18 Jan 8:52 pm CST |
Extended Forecast for
Saint Johns IL
Tonight
Low: 13 °F
Partly Cloudy
M.L.King Day
High: 22 °F
Increasing
CloudsMonday Night
Low: 11 °F
Mostly Clear
Tuesday
High: 36 °F
Sunny
Tuesday Night
Low: 26 °F
Partly Cloudy
Wednesday
High: 46 °F
Slight Chance
Showers then
Mostly SunnyWednesday Night
Low: 22 °F
Partly Cloudy
Thursday
High: 36 °F
Sunny
Thursday Night
Low: 22 °F
Partly Cloudy
Detailed Forecast
Tonight
Partly cloudy, with a low around 13. Southwest wind 10 to 14 mph becoming northwest after midnight. Winds could gust as high as 28 mph.
M.L.King Day
Increasing clouds, with a high near 22. Wind chill values as low as -3. Northwest wind 6 to 16 mph, with gusts as high as 28 mph.
Monday Night
Mostly clear, with a low around 11. Light and variable wind.
Tuesday
Sunny, with a high near 36. Light south southwest wind increasing to 5 to 10 mph in the morning.
Tuesday Night
Partly cloudy, with a low around 26. South wind 8 to 14 mph, with gusts as high as 24 mph.
Wednesday
A 20 percent chance of showers before noon. Partly sunny, with a high near 46. Southwest wind 7 to 14 mph, with gusts as high as 23 mph.
Wednesday Night
Partly cloudy, with a low around 22. West northwest wind around 6 mph.
Thursday
Sunny, with a high near 36. West northwest wind 5 to 8 mph becoming light and variable in the afternoon.
Thursday Night
Partly cloudy, with a low around 22. Calm wind becoming south southwest 5 to 7 mph after midnight.
Friday
Partly sunny, with a high near 40. South southwest wind 7 to 10 mph becoming north northeast in the afternoon.
Friday Night
A chance of snow showers. Mostly cloudy, with a low around 19. North northeast wind 7 to 10 mph.
Saturday
A chance of snow showers. Mostly cloudy, with a high near 29. North northeast wind around 11 mph, with gusts as high as 18 mph.
Saturday Night
A chance of snow showers. Mostly cloudy, with a low around 9. North wind around 10 mph.
Sunday
A slight chance of snow showers. Mostly sunny, with a high near 21. North wind 8 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
6:32 pm CST Jan 18, 2026
9pm CST Jan 18, 2026-6pm CST Jan 25, 2026
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