Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Thunderstorm in Vicinity Light Rain Fog/Mist
59°F
15°C
| Humidity | 100% |
| Wind Speed | E 7 mph |
| Barometer | 29.97 in (1014.7 mb) |
| Dewpoint | 59°F (15°C) |
| Visibility | 6.00 mi |
| Last update | 5 Mar 3:52 am CST |
Extended Forecast for
Saint Johns IL
Flood Watch until March 5, 12:00pm
NOW until 12:00pm Thu

Flood Watch
Overnight

Low: 59 °F
Showers and
Patchy FogThursday
High: 71 °F
Showers and
Patchy Fog
then Chance
T-stormsThursday Night
Low: 59 °F
Chance
T-storms then
Chance
Showers and
Patchy FogFriday
High: 77 °F
Fog then
Chance
ShowersFriday Night
Low: 61 °F
Slight Chance
Showers then
Showers
LikelySaturday
High: 70 °F
Showers then
Chance
ShowersSaturday Night

Low: 41 °F
Partly Cloudy
Sunday

High: 63 °F
Sunny
Detailed Forecast
Overnight
Showers and possibly a thunderstorm. Patchy fog. Steady temperature around 59. Calm wind becoming southeast around 6 mph. Chance of precipitation is 90%.
Thursday
Showers and thunderstorms before 3pm, then a slight chance of showers and thunderstorms after 4pm. Patchy fog before 10am. High near 71. Southeast wind 5 to 10 mph becoming west in the afternoon. Chance of precipitation is 90%.
Thursday Night
A chance of showers and thunderstorms before 3am, then a slight chance of showers between 3am and 4am. Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 59. Light and variable wind becoming south 5 to 7 mph in the evening. Chance of precipitation is 30%.
Friday
A 30 percent chance of showers after noon. Widespread fog before 7am. Otherwise, partly sunny, with a high near 77. South wind 8 to 18 mph, with gusts as high as 26 mph.
Friday Night
A slight chance of showers, then showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 61. South wind 13 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%.
Saturday
Showers and possibly a thunderstorm. High near 70. South southwest wind 9 to 14 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 80%.
Saturday Night
Partly cloudy, with a low around 41. Northwest wind 5 to 8 mph becoming calm after midnight.
Sunday
Sunny, with a high near 63. Calm wind becoming west around 5 mph.
Sunday Night
Mostly clear, with a low around 47. South southwest wind 3 to 6 mph.
Monday
Sunny, with a high near 73. South southwest wind 6 to 13 mph, with gusts as high as 20 mph.
Monday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 60. South southwest wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 76. South southwest wind 10 to 17 mph, with gusts as high as 25 mph.
Tuesday Night
Showers and possibly a thunderstorm. Mostly cloudy, with a low around 55. South southwest wind 15 to 17 mph, with gusts as high as 28 mph.
Wednesday
Showers. Mostly cloudy, with a high near 63. Southwest wind 15 to 17 mph becoming north northwest in the afternoon. Winds could gust as high as 26 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
3:51 am CST Mar 5, 2026
3am CST Mar 5, 2026-6pm CDT Mar 11, 2026



