Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Mostly Cloudy
69°F
21°C
| Humidity | 90% |
| Wind Speed | S 15 G 22 mph |
| Barometer | 29.94 in (1013.4 mb) |
| Dewpoint | 66°F (19°C) |
| Visibility | 8.00 mi |
| Last update | 10 Mar 8:52 am CDT |
Extended Forecast for
Saint Johns IL
Today

High: 79 °F
Mostly Cloudy
Tonight
Low: 65 °F
Slight Chance
T-storms then
Showers
LikelyWednesday

High: 70 °F⇓
Showers and
BreezyWednesday Night
Low: 34 °F
Chance
Showers and
Breezy then
Mostly CloudyThursday

High: 54 °F
Sunny
Thursday Night

Low: 43 °F
Partly Cloudy
Friday

High: 64 °F
Partly Sunny
Friday Night

Low: 40 °F
Partly Cloudy
Saturday

High: 68 °F
Sunny
Detailed Forecast
Today
Mostly cloudy, with a high near 79. South southwest wind 9 to 17 mph, with gusts as high as 26 mph.
Tonight
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 5am. Cloudy, with a low around 65. South southwest wind 15 to 17 mph, with gusts as high as 28 mph. Chance of precipitation is 60%.
Wednesday
Showers and thunderstorms before 1pm, then showers likely and possibly a thunderstorm between 1pm and 4pm, then showers likely after 4pm. Temperature falling to around 51 by 5pm. Breezy, with a south southwest wind 15 to 21 mph becoming northwest in the afternoon. Winds could gust as high as 29 mph. Chance of precipitation is 90%.
Wednesday Night
A 30 percent chance of showers before 7pm. Mostly cloudy, with a low around 34. Breezy, with a north northwest wind 15 to 20 mph decreasing to 8 to 13 mph after midnight. Winds could gust as high as 29 mph.
Thursday
Sunny, with a high near 54. North northwest wind around 6 mph becoming west southwest in the afternoon.
Thursday Night
Partly cloudy, with a low around 43. South wind 7 to 12 mph increasing to 13 to 18 mph after midnight. Winds could gust as high as 29 mph.
Friday
Partly sunny, with a high near 64. Southwest wind 9 to 16 mph, with gusts as high as 28 mph.
Friday Night
Partly cloudy, with a low around 40. North northwest wind around 6 mph becoming east after midnight.
Saturday
Sunny, with a high near 68. East southeast wind 7 to 14 mph becoming south in the afternoon. Winds could gust as high as 22 mph.
Saturday Night
Partly cloudy, with a low around 55. South wind 11 to 14 mph, with gusts as high as 25 mph.
Sunday
Showers and thunderstorms likely. Mostly cloudy, with a high near 66. Breezy, with a south southwest wind 15 to 20 mph becoming west northwest in the afternoon. Winds could gust as high as 30 mph.
Sunday Night
A chance of rain and snow showers. Mostly cloudy, with a low around 25. Blustery, with a northwest wind 16 to 21 mph, with gusts as high as 29 mph.
Monday
A slight chance of snow showers. Mostly sunny, with a high near 38. Northwest wind around 14 mph, with gusts as high as 22 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
8:01 am CDT Mar 10, 2026
9am CDT Mar 10, 2026-6pm CDT Mar 16, 2026



