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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Fair

70°F

21°C

Humidity 33%
Wind Speed S 12 mph
Barometer 29.95 in
Dewpoint 39°F (4°C)
Visibility 10.00 mi
Last update 27 Feb 1:52 pm CST
Extended Forecast for

Saint Johns IL

  • This Afternoon

    This Afternoon: Sunny, with a high near 71. South southwest wind 10 to 13 mph, with gusts as high as 20 mph.

    High: 71 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 40. South wind 5 to 10 mph becoming north northeast after midnight.

    Low: 40 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 68. Northeast wind 5 to 8 mph becoming south in the afternoon.

    High: 68 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: A 20 percent chance of showers before midnight. Partly cloudy, with a low around 35. South wind 6 to 10 mph becoming north after midnight.

    Low: 35 °F

    Slight Chance
    Showers then
    Mostly Clear

  • Sunday

    Sunday: Mostly cloudy, with a high near 49. Northeast wind around 10 mph, with gusts as high as 18 mph.

    High: 49 °F

    Mostly Cloudy

  • Sunday Night

    Sunday Night: Rain showers likely before 9pm, then rain likely, possibly mixed with snow showers between 9pm and 3am, then rain showers likely after 3am. Cloudy, with a low around 34. East northeast wind around 10 mph. Chance of precipitation is 70%.

    Low: 34 °F

    Rain/Snow
    Likely

  • Monday

    Monday: A 50 percent chance of showers, mainly before noon. Cloudy, with a high near 45. East wind 7 to 10 mph.

    High: 45 °F

    Chance
    Showers then
    Slight Chance
    Showers

  • Monday Night

    Monday Night: Showers likely, mainly after midnight. Cloudy, with a low around 40. East wind around 7 mph becoming south after midnight.

    Low: 40 °F

    Showers
    Likely

  • Tuesday

    Tuesday: Showers likely and possibly a thunderstorm. Cloudy, with a high near 62. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.

    High: 62 °F

    Showers
    Likely

Detailed Forecast

This Afternoon
Sunny, with a high near 71. South southwest wind 10 to 13 mph, with gusts as high as 20 mph.
Tonight
Mostly clear, with a low around 40. South wind 5 to 10 mph becoming north northeast after midnight.
Saturday
Mostly sunny, with a high near 68. Northeast wind 5 to 8 mph becoming south in the afternoon.
Saturday Night
A 20 percent chance of showers before midnight. Partly cloudy, with a low around 35. South wind 6 to 10 mph becoming north after midnight.
Sunday
Mostly cloudy, with a high near 49. Northeast wind around 10 mph, with gusts as high as 18 mph.
Sunday Night
Rain showers likely before 9pm, then rain likely, possibly mixed with snow showers between 9pm and 3am, then rain showers likely after 3am. Cloudy, with a low around 34. East northeast wind around 10 mph. Chance of precipitation is 70%.
Monday
A 50 percent chance of showers, mainly before noon. Cloudy, with a high near 45. East wind 7 to 10 mph.
Monday Night
Showers likely, mainly after midnight. Cloudy, with a low around 40. East wind around 7 mph becoming south after midnight.
Tuesday
Showers likely and possibly a thunderstorm. Cloudy, with a high near 62. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.
Tuesday Night
Showers likely, with thunderstorms also possible after midnight. Cloudy, with a low around 51. South southeast wind 7 to 9 mph.
Wednesday
Showers likely and possibly a thunderstorm. Cloudy, with a high near 65. South wind 9 to 11 mph, with gusts as high as 18 mph.
Wednesday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 53. South southwest wind 9 to 11 mph, with gusts as high as 20 mph.
Thursday
Showers likely. Mostly cloudy, with a high near 68. South southwest wind 10 to 14 mph, with gusts as high as 21 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:
12:56 pm CST Feb 27, 2026
Forecast Valid:
2pm CST Feb 27, 2026-6pm CST Mar 5, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation