Hazardous Weather Conditions
Current conditions at
Southern Illinois Airport (KMDH)
Lat: 37.78°NLon: 89.25°WElev: 400ft.
Fair
75°F
24°C
| Humidity | 94% |
| Wind Speed | S 5 mph |
| Barometer | 29.84 in (1010.2 mb) |
| Dewpoint | 73°F (23°C) |
| Visibility | 10.00 mi |
| Last update | 18 Jun 1:52 am CDT |
Extended Forecast for
Saint Johns IL
Lake Wind Advisory June 18, 11:00am until June 18, 07:00pm
Overnight
Low: 73 °F
Partly Cloudy
Wednesday
High: 88 °F
Chance
T-storms then
Severe
ThunderstormsWednesday Night
Low: 70 °F
Severe
Thunderstorms
then Chance
T-stormsJuneteenth
High: 85 °F
Mostly Sunny
Thursday Night
Low: 66 °F
Mostly Clear
Friday
High: 89 °F
Sunny
Friday Night
Low: 73 °F
Clear
Saturday
High: 93 °F
Sunny
Saturday Night
Low: 76 °F
Mostly Clear
Detailed Forecast
Overnight
Partly cloudy, with a low around 73. South wind around 7 mph.
Wednesday
Showers and thunderstorms likely, mainly between 3pm and 4pm. Some of the storms could be severe. Partly sunny, with a high near 88. Southwest wind 10 to 17 mph, with gusts as high as 26 mph. Chance of precipitation is 60%.
Wednesday Night
Showers and thunderstorms likely before 1am, then a slight chance of showers between 1am and 2am. Some of the storms could be severe. Mostly cloudy, with a low around 70. Southwest wind 6 to 13 mph, with gusts as high as 21 mph. Chance of precipitation is 70%.
Juneteenth
Mostly sunny, with a high near 85. Northwest wind around 7 mph.
Thursday Night
Mostly clear, with a low around 66. Calm wind.
Friday
Sunny, with a high near 89. Calm wind becoming south southwest 5 to 8 mph in the morning.
Friday Night
Clear, with a low around 73. South wind around 7 mph.
Saturday
Sunny, with a high near 93. South wind 7 to 11 mph, with gusts as high as 18 mph.
Saturday Night
Mostly clear, with a low around 76. South wind 6 to 9 mph.
Sunday
Sunny, with a high near 94. South wind 6 to 10 mph.
Sunday Night
Clear, with a low around 75. South wind 3 to 7 mph.
Monday
Sunny, with a high near 94. South wind 3 to 7 mph.
Monday Night
Mostly clear, with a low around 74. South wind around 6 mph becoming calm in the evening.
Tuesday
A slight chance of showers and thunderstorms. Sunny, with a high near 93. Calm wind becoming south around 6 mph in the afternoon.
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Saint Johns IL
38.03°N 89.21°W
38.03°N 89.21°W
2:00 am CDT Jun 18, 2025
2am CDT Jun 18, 2025-6pm CDT Jun 24, 2025
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