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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair and Windy

84°F

29°C

Humidity 44%
Wind Speed S 29 G 41 mph
Barometer 29.77 in (1007.5 mb)
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 26 Mar 4:52 pm CDT
Extended Forecast for

Saint Johns IL

  • Tonight

    Tonight: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 4am. Increasing clouds, with a low around 42. South southwest wind 13 to 18 mph becoming north after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 60%.

    Low: 42 °F

    Partly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers and thunderstorms likely, mainly before 11am. Cloudy, then gradual clearing during the afternoon, with a high near 53. North wind around 16 mph, with gusts as high as 28 mph. Chance of precipitation is 60%.

    High: 53 °F

    Showers
    Likely then
    Partly Sunny

  • Friday Night

    Friday Night: Patchy frost after 4am. Otherwise, mostly clear, with a low around 31. North wind 6 to 14 mph, with gusts as high as 23 mph.

    Low: 31 °F

    Mostly Clear
    then Patchy
    Frost

  • Saturday

    Saturday: Patchy frost before 8am. Otherwise, sunny, with a high near 56. North northeast wind around 6 mph becoming southeast in the afternoon.

    High: 56 °F

    Patchy Frost
    then Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 39. South southeast wind around 6 mph.

    Low: 39 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 67. South wind 6 to 11 mph, with gusts as high as 18 mph.

    High: 67 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 56. South wind 8 to 10 mph, with gusts as high as 20 mph.

    Low: 56 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 81. South southwest wind 11 to 15 mph, with gusts as high as 23 mph.

    High: 81 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 63. South wind 11 to 13 mph, with gusts as high as 23 mph.

    Low: 63 °F

    Mostly Cloudy

Detailed Forecast

Tonight
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 4am. Increasing clouds, with a low around 42. South southwest wind 13 to 18 mph becoming north after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 60%.
Friday
Showers and thunderstorms likely, mainly before 11am. Cloudy, then gradual clearing during the afternoon, with a high near 53. North wind around 16 mph, with gusts as high as 28 mph. Chance of precipitation is 60%.
Friday Night
Patchy frost after 4am. Otherwise, mostly clear, with a low around 31. North wind 6 to 14 mph, with gusts as high as 23 mph.
Saturday
Patchy frost before 8am. Otherwise, sunny, with a high near 56. North northeast wind around 6 mph becoming southeast in the afternoon.
Saturday Night
Partly cloudy, with a low around 39. South southeast wind around 6 mph.
Sunday
Partly sunny, with a high near 67. South wind 6 to 11 mph, with gusts as high as 18 mph.
Sunday Night
Partly cloudy, with a low around 56. South wind 8 to 10 mph, with gusts as high as 20 mph.
Monday
Mostly sunny, with a high near 81. South southwest wind 11 to 15 mph, with gusts as high as 23 mph.
Monday Night
Mostly cloudy, with a low around 63. South wind 11 to 13 mph, with gusts as high as 23 mph.
Tuesday
Partly sunny, with a high near 84. South southwest wind 13 to 16 mph, with gusts as high as 26 mph.
Tuesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 60. South southwest wind around 15 mph, with gusts as high as 25 mph.
Wednesday
A chance of showers and thunderstorms. Partly sunny, with a high near 78. South southwest wind 14 to 17 mph, with gusts as high as 25 mph.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 58. South wind around 14 mph, with gusts as high as 24 mph.
Thursday
A chance of showers and thunderstorms. Mostly cloudy, with a high near 72. South wind around 15 mph, with gusts as high as 23 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
4:02 pm CDT Mar 26, 2026
Forecast Valid:
5pm CDT Mar 26, 2026-6pm CDT Apr 2, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation