Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Overcast
66°F
19°C
| Humidity | 90% |
| Wind Speed | S 17 G 24 mph |
| Barometer | 30.00 in (1015.6 mb) |
| Dewpoint | 63°F (17°C) |
| Visibility | 10.00 mi |
| Last update | 5 Mar 11:52 am CST |
Extended Forecast for
Saint Johns IL
This Afternoon

High: 67 °F
Chance
ShowersTonight

Low: 59 °F
Chance
T-stormsFriday
High: 76 °F
Slight Chance
Showers then
Partly SunnyFriday Night
Low: 63 °F
Mostly Cloudy
then Showers
LikelySaturday
High: 72 °F
Showers then
Chance
T-stormsSaturday Night
Low: 41 °F
Slight Chance
Showers then
Partly CloudySunday

High: 65 °F
Mostly Sunny
Sunday Night

Low: 49 °F
Mostly Clear
Monday

High: 75 °F
Sunny
Detailed Forecast
This Afternoon
A 40 percent chance of showers and thunderstorms, mainly between 1pm and 4pm. Mostly cloudy, with a steady temperature around 67. Southwest wind 5 to 10 mph becoming light west.
Tonight
A chance of showers and thunderstorms. Mostly cloudy, with a low around 59. Calm wind becoming south southeast around 6 mph after midnight. Chance of precipitation is 40%.
Friday
A 20 percent chance of showers before 8am. Mostly sunny, with a high near 76. South wind 7 to 17 mph, with gusts as high as 25 mph.
Friday Night
Showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 63. South wind 11 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.
Saturday
Showers and possibly a thunderstorm before noon, then a chance of showers and thunderstorms after noon. High near 72. South southwest wind 10 to 14 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 80%.
Saturday Night
A 20 percent chance of showers before midnight. Partly cloudy, with a low around 41. Northwest wind 5 to 9 mph becoming calm after midnight.
Sunday
Mostly sunny, with a high near 65. Calm wind becoming southwest around 6 mph.
Sunday Night
Mostly clear, with a low around 49. South wind 3 to 6 mph.
Monday
Sunny, with a high near 75. South southwest wind 6 to 13 mph, with gusts as high as 20 mph.
Monday Night
A slight chance of showers, then a chance of showers and thunderstorms after midnight. Partly cloudy, with a low around 60. South southwest wind around 10 mph, with gusts as high as 18 mph.
Tuesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 76. South southwest wind 9 to 16 mph, with gusts as high as 24 mph.
Tuesday Night
Showers and possibly a thunderstorm. Mostly cloudy, with a low around 59. South wind around 15 mph, with gusts as high as 25 mph.
Wednesday
Showers. Mostly cloudy, with a high near 70. South southwest wind 14 to 16 mph becoming north northwest in the afternoon. Winds could gust as high as 24 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
10:51 am CST Mar 5, 2026
12pm CST Mar 5, 2026-6pm CDT Mar 11, 2026



