Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Overcast

31°F

-1°C

Humidity 76%
Wind Speed N 6 mph
Barometer 30.17 in (1022.1 mb)
Dewpoint 24°F (-4°C)
Visibility 10.00 mi
Wind Chill25°F (-4°C)
Last update 1 Dec 3:52 pm CST
Extended Forecast for

Saint Johns IL

Winter Weather Advisory December 1, 06:00pm until December 2, 06:00am
Click here for hazard details and duration
Winter Weather Advisory
  • This Afternoon

    This Afternoon: A 50 percent chance of snow.  Cloudy, with a high near 32. Light north northeast wind.

    High: 32 °F

    Chance Snow

  • Tonight

    Tonight: Snow, possibly mixed with freezing rain, mainly before 1am.  Low around 22. Calm wind becoming northwest 5 to 9 mph after midnight.  Chance of precipitation is 100%. Little or no ice accumulation expected.  New snow accumulation of 1 to 3 inches possible.

    Low: 22 °F

    Snow then
    Wintry Mix
    Likely

  • Tuesday

    Tuesday: Mostly sunny, with a high near 33. Northwest wind 5 to 7 mph becoming calm  in the afternoon.

    High: 33 °F

    Mostly 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: Mostly sunny, with a high near 42. South wind 5 to 10 mph.

    High: 42 °F

    Mostly Sunny

  • 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 5 to 11 mph, with gusts as high as 18 mph.

    High: 27 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 16. Light and variable wind.

    Low: 16 °F

    Partly Cloudy

  • Friday

    Friday: A slight chance of snow showers.  Mostly sunny, with a high near 39. Calm wind becoming south around 6 mph in the morning.

    High: 39 °F

    Slight Chance
    Snow Showers

Detailed Forecast

This Afternoon
A 50 percent chance of snow. Cloudy, with a high near 32. Light north northeast wind.
Tonight
Snow, possibly mixed with freezing rain, mainly before 1am. Low around 22. Calm wind becoming northwest 5 to 9 mph after midnight. Chance of precipitation is 100%. Little or no ice accumulation expected. New snow accumulation of 1 to 3 inches possible.
Tuesday
Mostly sunny, with a high near 33. 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
Mostly sunny, with a high near 42. South 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 5 to 11 mph, with gusts as high as 18 mph.
Thursday Night
Partly cloudy, with a low around 16. Light and variable wind.
Friday
A slight chance of snow showers. Mostly sunny, with a high near 39. Calm wind becoming south around 6 mph in the morning.
Friday Night
Partly cloudy, with a low around 25. Light southwest wind.
Saturday
Partly sunny, with a high near 42. Southwest wind 3 to 7 mph.
Saturday Night
Mostly cloudy, with a low around 28. Light and variable wind becoming west around 6 mph in the evening.
Sunday
Mostly cloudy, with a high near 40. North wind 6 to 9 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
3:16 pm CST Dec 1, 2025
4pm CST Dec 1, 2025-6pm CST Dec 7, 2025
 
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Additional Resources

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Hourly Weather Forecast

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