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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

41°F

5°C

Humidity 62%
Wind Speed SE 10 mph
Barometer 30.32 in (1026.8 mb)
Dewpoint 29°F (-2°C)
Visibility 10.00 mi
Wind Chill35°F (2°C)
Last update 24 Mar 4:52 am CDT
Extended Forecast for

Saint Johns IL

  • Today

    Today: Mostly sunny, with a high near 63. Southeast wind around 7 mph.

    High: 63 °F

    Mostly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 44. East wind around 6 mph becoming calm after midnight.

    Low: 44 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 74. Light south southeast wind becoming south southwest 5 to 10 mph in the morning.

    High: 74 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 61. South wind 8 to 11 mph, with gusts as high as 20 mph.

    Low: 61 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 85. South southwest wind 10 to 16 mph, with gusts as high as 24 mph.

    High: 85 °F

    Sunny

  • Thursday Night

    Thursday Night: A slight chance of showers, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 44. South southwest wind around 15 mph becoming north after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 60%.

    Low: 44 °F

    Slight Chance
    Showers then
    Showers
    Likely

  • Friday

    Friday: Showers likely, mainly before 1pm. Mostly cloudy, with a high near 54. North wind around 15 mph, with gusts as high as 23 mph. Chance of precipitation is 60%.

    High: 54 °F

    Showers
    Likely

  • Friday Night

    Friday Night: Mostly clear, with a low around 31. North wind 6 to 11 mph, with gusts as high as 20 mph.

    Low: 31 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 56. Northeast wind around 7 mph.

    High: 56 °F

    Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 63. Southeast wind around 7 mph.
Tonight
Mostly cloudy, with a low around 44. East wind around 6 mph becoming calm after midnight.
Wednesday
Mostly sunny, with a high near 74. Light south southeast wind becoming south southwest 5 to 10 mph in the morning.
Wednesday Night
Mostly clear, with a low around 61. South wind 8 to 11 mph, with gusts as high as 20 mph.
Thursday
Sunny, with a high near 85. South southwest wind 10 to 16 mph, with gusts as high as 24 mph.
Thursday Night
A slight chance of showers, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 44. South southwest wind around 15 mph becoming north after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 60%.
Friday
Showers likely, mainly before 1pm. Mostly cloudy, with a high near 54. North wind around 15 mph, with gusts as high as 23 mph. Chance of precipitation is 60%.
Friday Night
Mostly clear, with a low around 31. North wind 6 to 11 mph, with gusts as high as 20 mph.
Saturday
Sunny, with a high near 56. Northeast wind around 7 mph.
Saturday Night
Partly cloudy, with a low around 37. East wind 3 to 5 mph.
Sunday
Partly sunny, with a high near 65. South wind 5 to 8 mph.
Sunday Night
Mostly cloudy, with a low around 49. South wind around 7 mph.
Monday
Mostly sunny, with a high near 75. South wind 9 to 11 mph, with gusts as high as 20 mph.
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Forecast Area
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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 24, 2026
Forecast Valid:
5am CDT Mar 24, 2026-6pm CDT Mar 30, 2026
 
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Additional Resources

Radar & Satellite Image

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