Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Overcast
28°F
-2°C
| Humidity | 56% |
| Wind Speed | SW 5 mph |
| Barometer | 30.10 in (1019.5 mb) |
| Dewpoint | 14°F (-10°C) |
| Visibility | 10.00 mi |
| Wind Chill | 22°F (-6°C) |
| Last update | 17 Jan 8:52 am CST |
Extended Forecast for
Saint Johns IL
Today
High: 30 °F
Snow Showers
Likely then
Slight Chance
Snow ShowersTonight

Low: 13 °F
Mostly Clear
Sunday

High: 32 °F
Increasing
CloudsSunday Night

Low: 15 °F
Partly Cloudy
M.L.King Day

High: 23 °F
Mostly Sunny
Monday Night

Low: 11 °F
Mostly Clear
Tuesday

High: 36 °F
Sunny
Tuesday Night

Low: 28 °F
Mostly Clear
Wednesday

High: 46 °F
Partly Sunny
Detailed Forecast
Today
Snow showers likely, mainly before noon, then a chance of flurries after 1pm. Partly sunny, with a high near 30. Southwest wind 7 to 17 mph becoming west northwest in the morning. Winds could gust as high as 25 mph. Chance of precipitation is 60%. Total daytime snow accumulation of less than a half inch possible.
Tonight
Mostly clear, with a low around 13. West northwest wind 6 to 11 mph, with gusts as high as 21 mph.
Sunday
Increasing clouds, with a high near 32. South southwest wind 5 to 14 mph, with gusts as high as 21 mph.
Sunday Night
Partly cloudy, with a low around 15. South southwest wind 10 to 14 mph becoming northwest after midnight. Winds could gust as high as 23 mph.
M.L.King Day
Mostly sunny, with a high near 23. Northwest wind 7 to 14 mph, with gusts as high as 23 mph.
Monday Night
Mostly clear, with a low around 11. Northwest wind around 5 mph becoming calm.
Tuesday
Sunny, with a high near 36. South southwest wind 5 to 13 mph, with gusts as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 28. South wind 11 to 15 mph, with gusts as high as 25 mph.
Wednesday
Partly sunny, with a high near 46. South southwest wind 8 to 14 mph, with gusts as high as 24 mph.
Wednesday Night
A slight chance of rain showers before midnight, then a slight chance of snow showers. Partly cloudy, with a low around 22. West southwest wind around 7 mph becoming north after midnight.
Thursday
A slight chance of snow showers. Mostly sunny, with a high near 35. North northwest wind 6 to 8 mph.
Thursday Night
A slight chance of snow showers. Partly cloudy, with a low around 19. North wind around 6 mph becoming southeast after midnight.
Friday
A slight chance of rain and snow showers. Mostly sunny, with a high near 36. Southeast wind 6 to 9 mph becoming southwest in the afternoon.
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ABOUT THIS FORECAST
Point Forecast:
Saint Johns IL
38.03°N 89.24°W
38.03°N 89.24°W
8:07 am CST Jan 17, 2026
9am CST Jan 17, 2026-6pm CST Jan 23, 2026



