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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Overcast

27°F

-3°C

Humidity 89%
Wind Speed NW 10 mph
Barometer 30.05 in (1018.0 mb)
Dewpoint 24°F (-4°C)
Visibility 8.00 mi
Wind Chill18°F (-8°C)
Last update 2 Dec 1:52 am CST
Extended Forecast for

Saint Johns IL

Winter Weather Advisory December 2, 02:23am until December 2, 06:00am
Click here for hazard details and duration
Winter Weather Advisory
  •  
    Winter Weather Advisory December 2, 02:23am until December 2, 06:00am

    NOW until 6:00am Tue

    Winter Weather Advisory

  • Overnight

    Low: 22 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 32. Northwest wind 5 to 7 mph becoming calm in the afternoon.

    High: 32 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 21. Calm wind becoming south around 6 mph after midnight.

    Low: 21 °F

    Mostly Clear

  • Wednesday

    Wednesday: Increasing clouds, with a high near 42. South southwest wind 5 to 10 mph.

    High: 42 °F

    Increasing
    Clouds

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 18. Light and variable wind becoming north northwest 6 to 11 mph in the evening. Winds could gust as high as 18 mph.

    Low: 18 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 27. North wind 6 to 11 mph becoming light in the afternoon. Winds could gust as high as 18 mph.

    High: 27 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 16. Calm wind.

    Low: 16 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 38. Calm wind becoming south southwest 5 to 7 mph in the morning.

    High: 38 °F

    Mostly Sunny

Detailed Forecast

Overnight
Mostly cloudy, with a low around 22. Northwest wind around 7 mph.
Tuesday
Partly sunny, with a high near 32. Northwest wind 5 to 7 mph becoming calm in the afternoon.
Tuesday Night
Mostly clear, with a low around 21. Calm wind becoming south around 6 mph after midnight.
Wednesday
Increasing clouds, with a high near 42. South southwest wind 5 to 10 mph.
Wednesday Night
Mostly cloudy, with a low around 18. Light and variable wind becoming north northwest 6 to 11 mph in the evening. Winds could gust as high as 18 mph.
Thursday
Mostly sunny, with a high near 27. North wind 6 to 11 mph becoming light in the afternoon. Winds could gust as high as 18 mph.
Thursday Night
Partly cloudy, with a low around 16. Calm wind.
Friday
Mostly sunny, with a high near 38. Calm wind becoming south southwest 5 to 7 mph in the morning.
Friday Night
Partly cloudy, with a low around 24. South wind around 5 mph becoming light and variable in the evening.
Saturday
Partly sunny, with a high near 42. Light and variable wind becoming west 5 to 7 mph in the morning.
Saturday Night
Mostly cloudy, with a low around 26. East northeast wind 3 to 6 mph.
Sunday
Partly sunny, with a high near 37. North wind 6 to 8 mph.
Sunday Night
Mostly cloudy, with a low around 20. North wind around 6 mph.
Monday
Mostly sunny, with a high near 38. North northwest wind 5 to 7 mph becoming south southwest in the afternoon.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
12:51 am CST Dec 2, 2025
Forecast Valid:
2am CST Dec 2, 2025-6pm CST Dec 8, 2025
 
Forecast Discussion
 
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Additional Resources

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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