Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fog/Mist
47°F
8°C
| Humidity | 100% |
| Wind Speed | NE 3 mph |
| Barometer | 29.94 in (1013.8 mb) |
| Dewpoint | 47°F (8°C) |
| Visibility | 6.00 mi |
| Last update | 27 Dec 12:52 am CST |
Extended Forecast for
Saint Johns IL
Dense Fog Advisory until December 27, 09:00am
NOW until 9:00am Sat
Dense Fog Advisory
Overnight
Low: 47 °F
Patchy Fog
Saturday
High: 67 °F
Patchy Fog
then Mostly
CloudySaturday Night
Low: 62 °F⇑
Mostly Cloudy
Sunday
High: 71 °F
Slight Chance
Showers then
Showers
LikelySunday Night
Low: 23 °F
Blustery.
Showers then
Chance
Rain/SnowMonday
High: 27 °F
Mostly Sunny
and BlusteryMonday Night
Low: 19 °F
Mostly Clear
Tuesday
High: 35 °F
Sunny
Detailed Forecast
Overnight
Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 47. Light north northeast wind.
Saturday
Patchy fog before 9am. Otherwise, mostly cloudy, with a high near 67. Light east wind becoming southeast 5 to 9 mph in the morning.
Saturday Night
Mostly cloudy, with a temperature rising to around 65 by 5am. South southwest wind around 10 mph, with gusts as high as 18 mph.
Sunday
Showers likely, with thunderstorms also possible after 3pm. Cloudy, with a high near 71. South southwest wind 10 to 17 mph, with gusts as high as 26 mph. Chance of precipitation is 70%.
Sunday Night
Rain showers before midnight, then a chance of rain and snow showers between midnight and 3am, then a chance of snow showers after 3am. Some thunder is also possible. Low around 23. Blustery, with a southwest wind 18 to 22 mph becoming west northwest in the evening. Winds could gust as high as 31 mph. Chance of precipitation is 80%.
Monday
Mostly sunny, with a high near 27. Blustery, with a west northwest wind 15 to 22 mph, with gusts as high as 31 mph.
Monday Night
Mostly clear, with a low around 19. Northwest wind 9 to 14 mph, with gusts as high as 21 mph.
Tuesday
Sunny, with a high near 35. Northwest wind 7 to 10 mph becoming west southwest in the afternoon.
Tuesday Night
Mostly clear, with a low around 26. West southwest wind around 6 mph.
Wednesday
Mostly sunny, with a high near 43. West wind 6 to 10 mph.
Wednesday Night
Mostly cloudy, with a low around 22. Northwest wind around 7 mph.
New Year's Day
Mostly sunny, with a high near 32. North northwest wind 6 to 8 mph.
Thursday Night
Mostly cloudy, with a low around 17. North northwest wind 3 to 5 mph.
Friday
Mostly sunny, with a high near 31. North northwest wind 5 to 7 mph becoming east southeast in the afternoon.
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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
10:06 pm CST Dec 26, 2025
1am CST Dec 27, 2025-6pm CST Jan 2, 2026
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