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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

63°F

17°C

Humidity 56%
Wind Speed SW 13 mph
Barometer 30.18 in (1021.8 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Last update 10 Apr 2:52 am CDT
Extended Forecast for

Saint Johns IL

  • Overnight

    Overnight: Partly cloudy, with a steady temperature around 59. South southwest wind around 9 mph, with gusts as high as 18 mph.

    Low: 59 °F

    Partly Cloudy

  • Friday

    Friday: A chance of showers and thunderstorms before 4pm, then showers likely and possibly a thunderstorm between 4pm and 5pm, then a chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 77. South southwest wind 7 to 10 mph becoming north northwest in the afternoon. Winds could gust as high as 18 mph. Chance of precipitation is 60%.

    High: 77 °F

    Mostly Sunny
    then Showers
    Likely

  • Friday Night

    Friday Night: A 30 percent chance of showers and thunderstorms, mainly between 4am and 5am. Mostly cloudy, with a low around 53. North wind around 6 mph becoming light and variable.

    Low: 53 °F

    Chance
    Showers

  • Saturday

    Saturday: A chance of showers before 7am, then a slight chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 77. East northeast wind around 6 mph becoming south southeast in the afternoon. Chance of precipitation is 30%.

    High: 77 °F

    Chance
    Showers then
    Slight Chance
    T-storms

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 60. Southeast wind around 7 mph.

    Low: 60 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 81. South southwest wind 8 to 17 mph, with gusts as high as 28 mph.

    High: 81 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southwest wind around 14 mph, with gusts as high as 24 mph.

    Low: 66 °F

    Chance
    Showers

  • Monday

    Monday: A chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 82. South southwest wind 13 to 16 mph, with gusts as high as 25 mph.

    High: 82 °F

    Chance
    Showers then
    Chance
    T-storms

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 68. South southwest wind around 14 mph, with gusts as high as 22 mph.

    Low: 68 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Partly cloudy, with a steady temperature around 59. South southwest wind around 9 mph, with gusts as high as 18 mph.
Friday
A chance of showers and thunderstorms before 4pm, then showers likely and possibly a thunderstorm between 4pm and 5pm, then a chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 77. South southwest wind 7 to 10 mph becoming north northwest in the afternoon. Winds could gust as high as 18 mph. Chance of precipitation is 60%.
Friday Night
A 30 percent chance of showers and thunderstorms, mainly between 4am and 5am. Mostly cloudy, with a low around 53. North wind around 6 mph becoming light and variable.
Saturday
A chance of showers before 7am, then a slight chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 77. East northeast wind around 6 mph becoming south southeast in the afternoon. Chance of precipitation is 30%.
Saturday Night
Partly cloudy, with a low around 60. Southeast wind around 7 mph.
Sunday
Partly sunny, with a high near 81. South southwest wind 8 to 17 mph, with gusts as high as 28 mph.
Sunday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southwest wind around 14 mph, with gusts as high as 24 mph.
Monday
A chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 82. South southwest wind 13 to 16 mph, with gusts as high as 25 mph.
Monday Night
Mostly cloudy, with a low around 68. South southwest wind around 14 mph, with gusts as high as 22 mph.
Tuesday
A slight chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 85. South southwest wind 11 to 17 mph, with gusts as high as 25 mph.
Tuesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. South southwest wind around 14 mph, with gusts as high as 23 mph.
Wednesday
A chance of showers and thunderstorms. Partly sunny, with a high near 85. Southwest wind 13 to 15 mph, with gusts as high as 23 mph.
Wednesday Night
A chance of showers. Mostly cloudy, with a low around 61. Southwest wind 7 to 10 mph.
Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 80. South wind 7 to 11 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:
2:16 am CDT Apr 10, 2026
Forecast Valid:
3am CDT Apr 10, 2026-6pm CDT Apr 16, 2026
 
Forecast Discussion
 
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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