Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair
67°F
19°C
| Humidity | 73% |
| Wind Speed | S 10 mph |
| Barometer | 29.74 in (1006.7 mb) |
| Dewpoint | 58°F (14°C) |
| Visibility | 10.00 mi |
| Last update | 22 Mar 3:52 am CDT |
Extended Forecast for
Saint Johns IL
Today
High: 86 °F
Sunny then
Slight Chance
T-stormsTonight
Low: 36 °F
Chance
T-storms then
Mostly ClearMonday
High: 57 °F
Mostly Sunny
Monday Night
Low: 39 °F
Mostly Cloudy
Tuesday
High: 65 °F
Mostly Sunny
Tuesday Night
Low: 45 °F
Mostly Cloudy
Wednesday
High: 73 °F
Partly Sunny
Wednesday Night
Low: 60 °F
Slight Chance
T-stormsThursday
High: 85 °F
Sunny then
Slight Chance
T-storms
Detailed Forecast
Today
A 10 percent chance of showers and thunderstorms after 5pm. Sunny, with a high near 86. South southwest wind 9 to 16 mph, with gusts as high as 24 mph.
Tonight
A 40 percent chance of showers and thunderstorms, mainly before 10pm. Mostly cloudy during the early evening, then gradual clearing, with a low around 36. North wind 14 to 18 mph, with gusts as high as 31 mph.
Monday
Mostly sunny, with a high near 57. North northeast wind 9 to 11 mph, with gusts as high as 18 mph.
Monday Night
Mostly cloudy, with a low around 39. Northeast wind around 6 mph.
Tuesday
Mostly sunny, with a high near 65. Southeast wind around 6 mph.
Tuesday Night
Mostly cloudy, with a low around 45. Light southeast wind.
Wednesday
Partly sunny, with a high near 73. South southwest wind 5 to 9 mph.
Wednesday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 60. South wind 7 to 10 mph, with gusts as high as 18 mph.
Thursday
A slight chance of showers and thunderstorms after 1pm. Sunny, with a high near 85. Southwest wind 9 to 14 mph, with gusts as high as 21 mph.
Thursday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 43. Southwest wind 11 to 13 mph becoming north northeast after midnight. Winds could gust as high as 21 mph.
Friday
A chance of showers. Mostly cloudy, with a high near 53. North northeast wind 11 to 13 mph, with gusts as high as 20 mph.
Friday Night
A slight chance of showers. Partly cloudy, with a low around 34. North northeast wind 7 to 10 mph.
Saturday
Mostly sunny, with a high near 57. East northeast wind 6 to 8 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
1:26 am CDT Mar 22, 2026
4am CDT Mar 22, 2026-6pm CDT Mar 28, 2026
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