Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Light Rain
52°F
11°C
| Humidity | 66% |
| Wind Speed | NW 12 G 23 mph |
| Barometer | 29.98 in (1015.1 mb) |
| Dewpoint | 41°F (5°C) |
| Visibility | 10.00 mi |
| Wind Chill | 48°F (9°C) |
| Last update | 22 Mar 9:52 pm CDT |
Extended Forecast for
Saint Johns IL
Tonight
Low: 35 °F
Slight Chance
Showers then
Mostly ClearMonday
High: 55 °F
Sunny
Monday Night
Low: 38 °F
Mostly Cloudy
Tuesday
High: 62 °F
Mostly Sunny
Tuesday Night
Low: 43 °F
Partly Cloudy
Wednesday
High: 73 °F
Mostly Sunny
Wednesday Night
Low: 59 °F
Partly Cloudy
Thursday
High: 85 °F
Sunny
Thursday Night
Low: 42 °F
Chance
Showers
Detailed Forecast
Tonight
A 20 percent chance of showers before 11pm. Mostly cloudy, then gradually becoming clear, with a low around 35. North wind 8 to 16 mph, with gusts as high as 28 mph.
Monday
Sunny, with a high near 55. North northeast wind around 11 mph, with gusts as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 38. East northeast wind around 6 mph.
Tuesday
Mostly sunny, with a high near 62. East southeast wind around 6 mph.
Tuesday Night
Partly cloudy, with a low around 43. Light east southeast wind.
Wednesday
Mostly sunny, with a high near 73. Light south wind becoming south southwest 5 to 9 mph in the morning.
Wednesday Night
Partly cloudy, with a low around 59. South wind 7 to 10 mph, with gusts as high as 18 mph.
Thursday
Sunny, with a high near 85. South southwest wind 10 to 14 mph, with gusts as high as 21 mph.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 42. South southwest wind around 14 mph becoming north after midnight. Winds could gust as high as 23 mph.
Friday
A chance of showers. Partly sunny, with a high near 53. North wind around 14 mph, with gusts as high as 23 mph.
Friday Night
A slight chance of showers. Partly cloudy, with a low around 32. North wind 7 to 10 mph, with gusts as high as 18 mph.
Saturday
Sunny, with a high near 57. East wind around 7 mph.
Saturday Night
Partly cloudy, with a low around 37. South southeast wind 3 to 5 mph.
Sunday
Mostly sunny, with a high near 64. South southwest wind 5 to 9 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
10:31 pm CDT Mar 22, 2026
10pm CDT Mar 22, 2026-6pm CDT Mar 29, 2026
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