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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Mostly Cloudy and Windy

67°F

19°C

Humidity 63%
Wind Speed S 33 G 52 mph
Barometer 29.53 in (999.9 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 15 Mar 11:52 am CDT
Extended Forecast for

Saint Johns IL

High Wind Warning until March 15, 01:00pm
Click here for hazard details and duration
...
  •  
    High Wind Warning until March 15, 01:00pm

    NOW until 1:00pm Sun

    High Wind Warning

  • This Afternoon

    High: 68 °F

    Showers
    Likely and
    Breezy

  • Tonight

    Tonight: Showers and possibly a thunderstorm before 10pm, then a chance of showers between 10pm and 11pm. Some of the storms could produce heavy rainfall. Low around 24. Breezy, with a west wind 22 to 25 mph, with gusts as high as 43 mph. Chance of precipitation is 90%.

    Low: 24 °F

    Breezy. Heavy
    Rain then
    Mostly Cloudy

  • Monday

    Monday: A slight chance of snow showers between 9am and 1pm. Mostly cloudy, with a high near 33. Breezy, with a west northwest wind around 22 mph, with gusts as high as 38 mph. Chance of precipitation is 20%.

    High: 33 °F

    Slight Chance
    Snow Showers
    and Breezy

  • Monday Night

    Monday Night: Mostly cloudy, then gradually becoming clear, with a low around 15. West northwest wind 9 to 18 mph, with gusts as high as 26 mph.

    Low: 15 °F

    Decreasing
    Clouds

  • Tuesday

    Tuesday: Sunny, with a high near 38. Northwest wind around 7 mph becoming west southwest in the afternoon.

    High: 38 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of snow showers after 1am. Mostly cloudy, with a low around 30. Light south southeast wind becoming south 9 to 14 mph in the evening. Winds could gust as high as 22 mph.

    Low: 30 °F

    Mostly Cloudy
    then Slight
    Chance Snow
    Showers

  • Wednesday

    Wednesday: Partly sunny, with a high near 60. South wind 11 to 15 mph, with gusts as high as 23 mph.

    High: 60 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 42. South southwest wind around 7 mph.

    Low: 42 °F

    Partly Cloudy

Detailed Forecast

This Afternoon
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 5pm. Mostly cloudy, with a high near 68. Breezy, with a south wind 22 to 25 mph, with gusts as high as 47 mph. Chance of precipitation is 60%.
Tonight
Showers and possibly a thunderstorm before 10pm, then a chance of showers between 10pm and 11pm. Some of the storms could produce heavy rainfall. Low around 24. Breezy, with a west wind 22 to 25 mph, with gusts as high as 43 mph. Chance of precipitation is 90%.
Monday
A slight chance of snow showers between 9am and 1pm. Mostly cloudy, with a high near 33. Breezy, with a west northwest wind around 22 mph, with gusts as high as 38 mph. Chance of precipitation is 20%.
Monday Night
Mostly cloudy, then gradually becoming clear, with a low around 15. West northwest wind 9 to 18 mph, with gusts as high as 26 mph.
Tuesday
Sunny, with a high near 38. Northwest wind around 7 mph becoming west southwest in the afternoon.
Tuesday Night
A 20 percent chance of snow showers after 1am. Mostly cloudy, with a low around 30. Light south southeast wind becoming south 9 to 14 mph in the evening. Winds could gust as high as 22 mph.
Wednesday
Partly sunny, with a high near 60. South wind 11 to 15 mph, with gusts as high as 23 mph.
Wednesday Night
Partly cloudy, with a low around 42. South southwest wind around 7 mph.
Thursday
Sunny, with a high near 70. South southwest wind around 7 mph becoming west in the afternoon.
Thursday Night
Partly cloudy, with a low around 45. Northwest wind around 5 mph becoming southeast after midnight.
Friday
Mostly sunny, with a high near 73. Southwest wind 5 to 8 mph.
Friday Night
Partly cloudy, with a low around 49. Southwest wind 6 to 8 mph becoming northwest after midnight.
Saturday
Mostly sunny, with a high near 68. North northwest wind 8 to 10 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:
11:26 am CDT Mar 15, 2026
Forecast Valid:
12pm CDT Mar 15, 2026-6pm CDT Mar 21, 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