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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Partly Cloudy

71°F

22°C

Humidity 84%
Wind Speed E 3 mph
Barometer 29.91 in (1012.6 mb)
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Last update 21 Jun 7:52 am CDT
Extended Forecast for

2 Miles ENE Saint Johns IL

Flood Watch June 21, 01:00pm until June 22, 07:00am
Click here for hazard details and duration
Flood Watch

  • Today

    Today: A 50 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 89. South wind 5 to 10 mph increasing to 13 to 18 mph in the afternoon. Winds could gust as high as 26 mph.

    High: 89 °F

    Partly Sunny
    then Chance
    T-storms

  • Tonight

    Tonight: Showers and thunderstorms, mainly before 2am, then showers likely and possibly a thunderstorm after 5am. Low around 67. South southwest wind 9 to 16 mph, with gusts as high as 23 mph. Chance of precipitation is 90%.

    Low: 67 °F

    T-storms then
    Showers
    Likely

  • Monday

    Monday: Showers and thunderstorms likely before 11am, then a slight chance of showers between 11am and noon. Mostly cloudy, with a high near 80. Northwest wind 8 to 10 mph. Chance of precipitation is 60%.

    High: 80 °F

    Showers
    Likely then
    Mostly Cloudy

  • Monday Night

    Monday Night: Partly cloudy, with a low around 61. North wind 5 to 9 mph becoming calm in the evening.

    Low: 61 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 83. Light northeast wind.

    High: 83 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 63. Calm wind.

    Low: 63 °F

    Mostly Clear

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Calm wind.

    High: 86 °F

    Sunny then
    Slight Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 65. Calm wind.

    Low: 65 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: A chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Calm wind becoming west around 5 mph in the afternoon.

    High: 86 °F

    Mostly Sunny
    then Chance
    T-storms

Detailed Forecast

Today
A 50 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 89. South wind 5 to 10 mph increasing to 13 to 18 mph in the afternoon. Winds could gust as high as 26 mph.
Tonight
Showers and thunderstorms, mainly before 2am, then showers likely and possibly a thunderstorm after 5am. Low around 67. South southwest wind 9 to 16 mph, with gusts as high as 23 mph. Chance of precipitation is 90%.
Monday
Showers and thunderstorms likely before 11am, then a slight chance of showers between 11am and noon. Mostly cloudy, with a high near 80. Northwest wind 8 to 10 mph. Chance of precipitation is 60%.
Monday Night
Partly cloudy, with a low around 61. North wind 5 to 9 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 83. Light northeast wind.
Tuesday Night
Mostly clear, with a low around 63. Calm wind.
Wednesday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Calm wind.
Wednesday Night
A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 65. Calm wind.
Thursday
A chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. Calm wind becoming west around 5 mph in the afternoon.
Thursday Night
A slight chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 64. Northwest wind around 5 mph becoming calm in the evening.
Friday
A chance of showers and thunderstorms. Mostly sunny, with a high near 86. Calm wind.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. Light south wind.
Saturday
A chance of showers and thunderstorms. Partly sunny, with a high near 89. South wind 5 to 13 mph, with gusts as high as 20 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
2 Miles ENE Saint Johns IL
 38.03°N 89.19°W
Last Update:
7:16 am CDT Jun 21, 2026
Forecast Valid:
8am CDT Jun 21, 2026-6pm CDT Jun 27, 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