Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair
60°F
16°C
| Humidity | 96% |
| Wind Speed | S 7 mph |
| Barometer | 29.94 in (1013.7 mb) |
| Dewpoint | 59°F (15°C) |
| Visibility | 10.00 mi |
| Last update | 16 Apr 7:52 am CDT |
Extended Forecast for
Saint Johns IL
Today
High: 81 °F
Partly Sunny
then Slight
Chance
T-stormsTonight
Low: 59 °F
Mostly Clear
Friday
High: 85 °F
Mostly Sunny
then Chance
T-stormsFriday Night
Low: 54 °F
Chance
T-storms then
Showers
LikelySaturday
High: 66 °F
Showers
LikelySaturday Night
Low: 40 °F
Slight Chance
ShowersSunday
High: 65 °F
Sunny
Sunday Night
Low: 42 °F
Clear
Monday
High: 71 °F
Sunny
Detailed Forecast
Today
A 20 percent chance of showers and thunderstorms after 2pm. Mostly cloudy, then gradually becoming sunny, with a high near 81. Southwest wind 7 to 10 mph.
Tonight
Mostly clear, with a low around 59. South wind 3 to 6 mph.
Friday
A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 85. South wind 5 to 14 mph, with gusts as high as 22 mph.
Friday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 54. South wind around 14 mph, with gusts as high as 22 mph. Chance of precipitation is 70%.
Saturday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 66. West southwest wind 13 to 15 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 70%.
Saturday Night
A 20 percent chance of showers before 1am. Mostly clear, with a low around 40. Northwest wind 6 to 11 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 65. West northwest wind 6 to 11 mph, with gusts as high as 18 mph.
Sunday Night
Clear, with a low around 42. North northwest wind around 6 mph becoming southeast after midnight.
Monday
Sunny, with a high near 71. South wind 6 to 9 mph.
Monday Night
Mostly clear, with a low around 50. South wind around 7 mph.
Tuesday
Mostly sunny, with a high near 76. South southwest wind 7 to 13 mph, with gusts as high as 20 mph.
Tuesday Night
A slight chance of showers. Partly cloudy, with a low around 54. South southwest wind around 8 mph.
Wednesday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 78. South southwest wind 7 to 11 mph, with gusts as high as 18 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
6:51 am CDT Apr 16, 2026
8am CDT Apr 16, 2026-6pm CDT Apr 22, 2026
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