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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

42°F

6°C

Humidity 68%
Wind Speed NE 5 mph
Barometer 30.10 in (1019.4 mb)
Dewpoint 32°F (0°C)
Visibility 10.00 mi
Wind Chill39°F (4°C)
Last update 14 Mar 5:52 am CDT
Extended Forecast for

Saint Johns IL

  • Today

    Today: Mostly sunny, with a high near 66. East northeast wind 6 to 11 mph becoming south southeast in the afternoon. Winds could gust as high as 18 mph.

    High: 66 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 53. Southeast wind 8 to 15 mph, with gusts as high as 25 mph.

    Low: 53 °F

    Partly Cloudy

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm, mainly after 4pm. Mostly cloudy, with a high near 70. Breezy, with a south wind 20 to 28 mph, with gusts as high as 40 mph. Chance of precipitation is 70%.

    High: 70 °F

    Breezy.
    Mostly Cloudy
    then Showers
    Likely

  • Sunday Night

    Sunday Night: Rain showers before 1am, then a chance of snow showers. Some thunder is also possible. Low around 24. Breezy, with a south southwest wind 23 to 25 mph becoming west northwest after midnight. Winds could gust as high as 38 mph. Chance of precipitation is 90%.

    Low: 24 °F

    Breezy.
    Showers then
    Rain/Snow

  • Monday

    Monday: Mostly cloudy, with a high near 31. Blustery, with a west northwest wind around 22 mph, with gusts as high as 34 mph.

    High: 31 °F

    Mostly Cloudy
    and Blustery

  • Monday Night

    Monday Night: Partly cloudy, with a low around 14. Blustery, with a west northwest wind 15 to 20 mph decreasing to 9 to 14 mph after midnight. Winds could gust as high as 29 mph.

    Low: 14 °F

    Partly Cloudy
    and Blustery
    then Mostly
    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 37. West northwest wind around 7 mph.

    High: 37 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A slight chance of snow showers after 1am. Mostly cloudy, with a low around 28. South southeast wind 5 to 14 mph, with gusts as high as 24 mph.

    Low: 28 °F

    Mostly Cloudy
    then Slight
    Chance Snow
    Showers

  • Wednesday

    Wednesday: Partly sunny, with a high near 60. South southwest wind 13 to 16 mph, with gusts as high as 25 mph.

    High: 60 °F

    Partly Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 66. East northeast wind 6 to 11 mph becoming south southeast in the afternoon. Winds could gust as high as 18 mph.
Tonight
Partly cloudy, with a low around 53. Southeast wind 8 to 15 mph, with gusts as high as 25 mph.
Sunday
Showers likely and possibly a thunderstorm, mainly after 4pm. Mostly cloudy, with a high near 70. Breezy, with a south wind 20 to 28 mph, with gusts as high as 40 mph. Chance of precipitation is 70%.
Sunday Night
Rain showers before 1am, then a chance of snow showers. Some thunder is also possible. Low around 24. Breezy, with a south southwest wind 23 to 25 mph becoming west northwest after midnight. Winds could gust as high as 38 mph. Chance of precipitation is 90%.
Monday
Mostly cloudy, with a high near 31. Blustery, with a west northwest wind around 22 mph, with gusts as high as 34 mph.
Monday Night
Partly cloudy, with a low around 14. Blustery, with a west northwest wind 15 to 20 mph decreasing to 9 to 14 mph after midnight. Winds could gust as high as 29 mph.
Tuesday
Sunny, with a high near 37. West northwest wind around 7 mph.
Tuesday Night
A slight chance of snow showers after 1am. Mostly cloudy, with a low around 28. South southeast wind 5 to 14 mph, with gusts as high as 24 mph.
Wednesday
Partly sunny, with a high near 60. South southwest wind 13 to 16 mph, with gusts as high as 25 mph.
Wednesday Night
Mostly clear, with a low around 40. South wind 5 to 8 mph.
Thursday
Sunny, with a high near 71. Southwest wind around 6 mph.
Thursday Night
Partly cloudy, with a low around 47. South southwest wind around 6 mph.
Friday
Sunny, with a high near 70. Southwest wind 6 to 9 mph becoming west northwest in the afternoon.
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ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
1:26 am CDT Mar 14, 2026
Forecast Valid:
6am CDT Mar 14, 2026-6pm CDT Mar 20, 2026
 
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Additional Resources

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Chance of Precipitation