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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair and Windy

63°F

17°C

Humidity 68%
Wind Speed S 32 G 43 mph
Barometer 29.59 in (1001.7 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Last update 15 Mar 7:52 am CDT
Extended Forecast for

Saint Johns IL

Wind Advisory March 15, 10:00am until March 16, 07:00am
Click here for hazard details and duration
Wind Advisory

  • Today

    Today: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 3pm. High near 68. Breezy, with a south wind 20 to 26 mph, with gusts as high as 41 mph. Chance of precipitation is 80%.

    High: 68 °F

    Breezy.
    Mostly Cloudy
    then Showers

  • Tonight

    Tonight: Showers and possibly a thunderstorm before 9pm, then a chance of showers between 9pm and 10pm. Low around 24. Breezy, with a west northwest wind 23 to 26 mph, with gusts as high as 43 mph. Chance of precipitation is 90%.

    Low: 24 °F

    Showers and
    Breezy then
    Mostly Cloudy
    and Blustery

  • Monday

    Monday: Mostly cloudy, with a high near 33. Breezy, with a west northwest wind 20 to 22 mph, with gusts as high as 33 mph.

    High: 33 °F

    Mostly Cloudy
    and Breezy

  • Monday Night

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

    Low: 15 °F

    Mostly Clear

  • 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

  • Thursday

    Thursday: Sunny, with a high near 70. South southwest wind around 7 mph becoming west in the afternoon.

    High: 70 °F

    Sunny

Detailed Forecast

Today
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 3pm. High near 68. Breezy, with a south wind 20 to 26 mph, with gusts as high as 41 mph. Chance of precipitation is 80%.
Tonight
Showers and possibly a thunderstorm before 9pm, then a chance of showers between 9pm and 10pm. Low around 24. Breezy, with a west northwest wind 23 to 26 mph, with gusts as high as 43 mph. Chance of precipitation is 90%.
Monday
Mostly cloudy, with a high near 33. Breezy, with a west northwest wind 20 to 22 mph, with gusts as high as 33 mph.
Monday Night
Mostly 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:
6:21 am CDT Mar 15, 2026
Forecast Valid:
8am 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