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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

67°F

19°C

Humidity 81%
Wind Speed S 20 mph
Barometer 29.85 in (1010.8 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 9 Mar 7:52 pm CDT
Extended Forecast for

Saint Johns IL

  • Tonight

    Tonight: Mostly cloudy, with a low around 62. South southwest wind 9 to 13 mph, with gusts as high as 22 mph.

    Low: 62 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: A 10 percent chance of showers after 5pm. Partly sunny, with a high near 78. South southwest wind 8 to 16 mph, with gusts as high as 24 mph.

    High: 78 °F

    Partly Sunny
    then Slight
    Chance
    Showers

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Low around 64. South southwest wind 14 to 17 mph, with gusts as high as 26 mph. Chance of precipitation is 80%.

    Low: 64 °F

    Chance
    T-storms then
    Showers

  • Wednesday

    Wednesday: Showers and possibly a thunderstorm. High near 71. South southwest wind 15 to 17 mph becoming northwest in the afternoon. Winds could gust as high as 26 mph. Chance of precipitation is 100%.

    High: 71 °F

    Showers

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 34. Breezy, with a north northwest wind 15 to 20 mph decreasing to 9 to 14 mph after midnight. Winds could gust as high as 29 mph.

    Low: 34 °F

    Mostly Cloudy
    and Breezy
    then Mostly
    Cloudy

  • Thursday

    Thursday: Sunny, with a high near 53. North northwest wind around 6 mph becoming west southwest in the afternoon.

    High: 53 °F

    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 42. South wind 6 to 15 mph, with gusts as high as 25 mph.

    Low: 42 °F

    Partly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 65. Southwest wind 9 to 14 mph, with gusts as high as 24 mph.

    High: 65 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 41. North northwest wind around 6 mph becoming east after midnight.

    Low: 41 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 62. South southwest wind 9 to 13 mph, with gusts as high as 22 mph.
Tuesday
A 10 percent chance of showers after 5pm. Partly sunny, with a high near 78. South southwest wind 8 to 16 mph, with gusts as high as 24 mph.
Tuesday Night
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Low around 64. South southwest wind 14 to 17 mph, with gusts as high as 26 mph. Chance of precipitation is 80%.
Wednesday
Showers and possibly a thunderstorm. High near 71. South southwest wind 15 to 17 mph becoming northwest in the afternoon. Winds could gust as high as 26 mph. Chance of precipitation is 100%.
Wednesday Night
Mostly cloudy, with a low around 34. Breezy, with a north northwest wind 15 to 20 mph decreasing to 9 to 14 mph after midnight. Winds could gust as high as 29 mph.
Thursday
Sunny, with a high near 53. North northwest wind around 6 mph becoming west southwest in the afternoon.
Thursday Night
Partly cloudy, with a low around 42. South wind 6 to 15 mph, with gusts as high as 25 mph.
Friday
Mostly cloudy, with a high near 65. Southwest wind 9 to 14 mph, with gusts as high as 24 mph.
Friday Night
Mostly cloudy, with a low around 41. North northwest wind around 6 mph becoming east after midnight.
Saturday
Mostly sunny, with a high near 69. East wind 7 to 11 mph becoming south in the afternoon. Winds could gust as high as 20 mph.
Saturday Night
Mostly clear, with a low around 52. South southwest wind 10 to 14 mph, with gusts as high as 24 mph.
Sunday
A chance of showers. Partly sunny, with a high near 66. South southwest wind 14 to 18 mph becoming west northwest in the afternoon. Winds could gust as high as 28 mph.
Sunday Night
A chance of rain and snow showers. Partly cloudy, with a low around 30. Northwest wind 14 to 18 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 44. North northwest wind 10 to 13 mph, with gusts as high as 20 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
7:51 pm CDT Mar 9, 2026
Forecast Valid:
8pm CDT Mar 9, 2026-6pm CDT Mar 16, 2026
 
Forecast Discussion
 
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Additional Resources

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Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation