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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

60°F

16°C

Humidity 46%
Wind Speed S 7 mph
Barometer 29.96 in (1014.6 mb)
Dewpoint 39°F (4°C)
Visibility 10.00 mi
Last update 7 Jan 3:52 pm CST
Extended Forecast for

Saint Johns IL

  • This Afternoon

    This Afternoon: Partly sunny, with a high near 63. South wind 3 to 5 mph.

    High: 63 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 44. South southeast wind 5 to 7 mph.

    Low: 44 °F

    Mostly Cloudy

  • Thursday

    Thursday: Showers likely, mainly after noon. Cloudy, with a high near 66. Breezy, with a south wind 8 to 13 mph increasing to 16 to 21 mph in the afternoon. Winds could gust as high as 29 mph. Chance of precipitation is 60%.

    High: 66 °F

    Chance
    Showers then
    Showers
    Likely and
    Breezy

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm before 3am, then showers likely. Low around 57. Breezy, with a south wind 17 to 22 mph decreasing to 11 to 16 mph after midnight. Winds could gust as high as 32 mph. Chance of precipitation is 90%.

    Low: 57 °F

    Showers and
    Breezy then
    Showers
    Likely

  • Friday

    Friday: Partly sunny, with a high near 63. South southwest wind 7 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph.

    High: 63 °F

    Partly Sunny

  • Friday Night

    Friday Night: A 40 percent chance of showers. Mostly cloudy, with a low around 42. North northeast wind 5 to 8 mph.

    Low: 42 °F

    Chance
    Showers

  • Saturday

    Saturday: A 20 percent chance of showers before noon. Partly sunny, with a high near 46. West northwest wind 9 to 14 mph, with gusts as high as 22 mph.

    High: 46 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 26. West wind around 11 mph, with gusts as high as 20 mph.

    Low: 26 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 36. Northwest wind 6 to 14 mph, with gusts as high as 21 mph.

    High: 36 °F

    Sunny

Detailed Forecast

This Afternoon
Partly sunny, with a high near 63. South wind 3 to 5 mph.
Tonight
Mostly cloudy, with a low around 44. South southeast wind 5 to 7 mph.
Thursday
Showers likely, mainly after noon. Cloudy, with a high near 66. Breezy, with a south wind 8 to 13 mph increasing to 16 to 21 mph in the afternoon. Winds could gust as high as 29 mph. Chance of precipitation is 60%.
Thursday Night
Showers and possibly a thunderstorm before 3am, then showers likely. Low around 57. Breezy, with a south wind 17 to 22 mph decreasing to 11 to 16 mph after midnight. Winds could gust as high as 32 mph. Chance of precipitation is 90%.
Friday
Partly sunny, with a high near 63. South southwest wind 7 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph.
Friday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 42. North northeast wind 5 to 8 mph.
Saturday
A 20 percent chance of showers before noon. Partly sunny, with a high near 46. West northwest wind 9 to 14 mph, with gusts as high as 22 mph.
Saturday Night
Partly cloudy, with a low around 26. West wind around 11 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 36. Northwest wind 6 to 14 mph, with gusts as high as 21 mph.
Sunday Night
Mostly clear, with a low around 22. Northwest wind around 5 mph becoming calm.
Monday
Sunny, with a high near 44. South southwest wind 5 to 10 mph.
Monday Night
Mostly clear, with a low around 31. Southwest wind around 8 mph.
Tuesday
Mostly sunny, with a high near 51. Southwest wind 7 to 10 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Saint Johns IL
 38.03°N 89.24°W
Last Update:
3:16 pm CST Jan 7, 2026
Forecast Valid:
4pm CST Jan 7, 2026-6pm CST Jan 13, 2026
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation