Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Overcast
31°F
-1°C
| Humidity | 76% |
| Wind Speed | N 6 mph |
| Barometer | 30.17 in (1022.1 mb) |
| Dewpoint | 24°F (-4°C) |
| Visibility | 10.00 mi |
| Wind Chill | 25°F (-4°C) |
| Last update | 1 Dec 3:52 pm CST |
Extended Forecast for
Saint Johns IL
Winter Weather Advisory December 1, 06:00pm until December 2, 06:00am
This Afternoon

High: 32 °F
Chance Snow
Tonight
Low: 22 °F
Snow then
Wintry Mix
LikelyTuesday

High: 33 °F
Mostly Sunny
Tuesday Night

Low: 21 °F
Mostly Clear
Wednesday

High: 42 °F
Mostly Sunny
Wednesday Night

Low: 18 °F
Mostly Cloudy
Thursday

High: 27 °F
Mostly Sunny
Thursday Night

Low: 16 °F
Partly Cloudy
Friday

High: 39 °F
Slight Chance
Snow Showers
Detailed Forecast
This Afternoon
A 50 percent chance of snow. Cloudy, with a high near 32. Light north northeast wind.
Tonight
Snow, possibly mixed with freezing rain, mainly before 1am. Low around 22. Calm wind becoming northwest 5 to 9 mph after midnight. Chance of precipitation is 100%. Little or no ice accumulation expected. New snow accumulation of 1 to 3 inches possible.
Tuesday
Mostly sunny, with a high near 33. Northwest wind 5 to 7 mph becoming calm in the afternoon.
Tuesday Night
Mostly clear, with a low around 21. Calm wind becoming south around 6 mph after midnight.
Wednesday
Mostly sunny, with a high near 42. South wind 5 to 10 mph.
Wednesday Night
Mostly cloudy, with a low around 18. Light and variable wind becoming north northwest 6 to 11 mph in the evening. Winds could gust as high as 18 mph.
Thursday
Mostly sunny, with a high near 27. North wind 5 to 11 mph, with gusts as high as 18 mph.
Thursday Night
Partly cloudy, with a low around 16. Light and variable wind.
Friday
A slight chance of snow showers. Mostly sunny, with a high near 39. Calm wind becoming south around 6 mph in the morning.
Friday Night
Partly cloudy, with a low around 25. Light southwest wind.
Saturday
Partly sunny, with a high near 42. Southwest wind 3 to 7 mph.
Saturday Night
Mostly cloudy, with a low around 28. Light and variable wind becoming west around 6 mph in the evening.
Sunday
Mostly cloudy, with a high near 40. North wind 6 to 9 mph.
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ABOUT THIS FORECAST
Point Forecast:
Saint Johns IL
38.03°N 89.24°W
38.03°N 89.24°W
3:16 pm CST Dec 1, 2025
4pm CST Dec 1, 2025-6pm CST Dec 7, 2025



