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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

58°F

14°C

Humidity 42%
Wind Speed W 12 G 21 mph
Barometer 29.96 in (1014.6 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Last update 13 Mar 12:52 pm CDT
Extended Forecast for

Saint Johns IL

  • This Afternoon

    This Afternoon: Mostly cloudy early, then becoming sunny, with a high near 63. West northwest wind 11 to 14 mph, with gusts as high as 22 mph.

    High: 63 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 37. Northwest wind around 6 mph becoming light and variable.

    Low: 37 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 65. East wind 6 to 11 mph becoming south southeast in the afternoon. Winds could gust as high as 18 mph.

    High: 65 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 54. South southeast wind 8 to 14 mph, with gusts as high as 24 mph.

    Low: 54 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm, mainly after 4pm. Mostly cloudy, with a high near 71. Breezy, with a south wind 18 to 28 mph, with gusts as high as 41 mph. Chance of precipitation is 70%.

    High: 71 °F

    Breezy.
    Mostly Cloudy
    then Showers
    Likely

  • Sunday Night

    Sunday Night: Rain showers before 1am, then a chance of rain and snow showers between 1am and 4am, then a chance of snow showers after 4am. Some thunder is also possible. Low around 25. Breezy, with a south southwest wind 22 to 25 mph becoming west northwest after midnight. Winds could gust as high as 43 mph. Chance of precipitation is 100%.

    Low: 25 °F

    Breezy.
    Showers then
    Rain/Snow

  • Monday

    Monday: A 20 percent chance of snow showers before 1pm. Mostly cloudy, with a high near 31. Blustery, with a west northwest wind around 22 mph, with gusts as high as 33 mph.

    High: 31 °F

    Slight Chance
    Snow Showers
    and Blustery

  • Monday Night

    Monday Night: Mostly clear, with a low around 14. West northwest wind 9 to 18 mph, with gusts as high as 26 mph.

    Low: 14 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 38. West northwest wind around 7 mph.

    High: 38 °F

    Sunny

Detailed Forecast

This Afternoon
Mostly cloudy early, then becoming sunny, with a high near 63. West northwest wind 11 to 14 mph, with gusts as high as 22 mph.
Tonight
Mostly clear, with a low around 37. Northwest wind around 6 mph becoming light and variable.
Saturday
Mostly sunny, with a high near 65. East wind 6 to 11 mph becoming south southeast in the afternoon. Winds could gust as high as 18 mph.
Saturday Night
Increasing clouds, with a low around 54. South southeast wind 8 to 14 mph, with gusts as high as 24 mph.
Sunday
Showers likely and possibly a thunderstorm, mainly after 4pm. Mostly cloudy, with a high near 71. Breezy, with a south wind 18 to 28 mph, with gusts as high as 41 mph. Chance of precipitation is 70%.
Sunday Night
Rain showers before 1am, then a chance of rain and snow showers between 1am and 4am, then a chance of snow showers after 4am. Some thunder is also possible. Low around 25. Breezy, with a south southwest wind 22 to 25 mph becoming west northwest after midnight. Winds could gust as high as 43 mph. Chance of precipitation is 100%.
Monday
A 20 percent chance of snow showers before 1pm. Mostly cloudy, with a high near 31. Blustery, with a west northwest wind around 22 mph, with gusts as high as 33 mph.
Monday Night
Mostly clear, with a low around 14. West northwest wind 9 to 18 mph, with gusts as high as 26 mph.
Tuesday
Sunny, with a high near 38. West northwest wind around 7 mph.
Tuesday Night
A slight chance of rain and snow showers after 1am. Mostly cloudy, with a low around 28. South wind 5 to 11 mph, with gusts as high as 21 mph.
Wednesday
Partly sunny, with a high near 58. South southwest wind around 14 mph, with gusts as high as 23 mph.
Wednesday Night
Mostly clear, with a low around 40. South southwest wind around 7 mph.
Thursday
Sunny, with a high near 68. West wind 5 to 7 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
12:52 pm CDT Mar 13, 2026
Forecast Valid:
1pm CDT Mar 13, 2026-6pm CDT Mar 19, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation