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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Overcast

63°F

17°C

Humidity 84%
Wind Speed S 16 G 22 mph
Barometer 29.61 in (1002.4 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 19 Feb 10:52 am CST
Extended Forecast for

Saint Johns IL

  • Today

    Today: A 50 percent chance of showers and thunderstorms, mainly before 5pm. Partly sunny, with a high near 68. South wind 9 to 15 mph, with gusts as high as 28 mph.

    High: 68 °F

    Chance
    T-storms

  • Tonight

    Tonight: Mostly clear, with a low around 36. South wind 11 to 16 mph becoming west in the evening. Winds could gust as high as 33 mph.

    Low: 36 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 52. West wind 7 to 16 mph, with gusts as high as 28 mph.

    High: 52 °F

    Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 32. Calm wind becoming north around 6 mph after midnight.

    Low: 32 °F

    Partly Cloudy

  • Saturday

    Saturday: A 20 percent chance of showers after noon. Mostly sunny, with a high near 48. North wind 6 to 9 mph.

    High: 48 °F

    Mostly Sunny
    then Slight
    Chance
    Showers

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 25. Northwest wind 8 to 10 mph, with gusts as high as 20 mph.

    Low: 25 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 40. Northwest wind 11 to 17 mph, with gusts as high as 26 mph.

    High: 40 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 20. North northwest wind around 11 mph, with gusts as high as 20 mph.

    Low: 20 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 36. North northwest wind 7 to 13 mph, with gusts as high as 21 mph.

    High: 36 °F

    Sunny

Detailed Forecast

Today
A 50 percent chance of showers and thunderstorms, mainly before 5pm. Partly sunny, with a high near 68. South wind 9 to 15 mph, with gusts as high as 28 mph.
Tonight
Mostly clear, with a low around 36. South wind 11 to 16 mph becoming west in the evening. Winds could gust as high as 33 mph.
Friday
Sunny, with a high near 52. West wind 7 to 16 mph, with gusts as high as 28 mph.
Friday Night
Partly cloudy, with a low around 32. Calm wind becoming north around 6 mph after midnight.
Saturday
A 20 percent chance of showers after noon. Mostly sunny, with a high near 48. North wind 6 to 9 mph.
Saturday Night
Mostly clear, with a low around 25. Northwest wind 8 to 10 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 40. Northwest wind 11 to 17 mph, with gusts as high as 26 mph.
Sunday Night
Mostly clear, with a low around 20. North northwest wind around 11 mph, with gusts as high as 20 mph.
Monday
Sunny, with a high near 36. North northwest wind 7 to 13 mph, with gusts as high as 21 mph.
Monday Night
Mostly clear, with a low around 19. North northwest wind around 5 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 47. Light south southwest wind increasing to 8 to 13 mph in the morning. Winds could gust as high as 21 mph.
Tuesday Night
Mostly cloudy, with a low around 37. South southwest wind 11 to 14 mph, with gusts as high as 25 mph.
Wednesday
Mostly cloudy, with a high near 58. South southwest wind 13 to 17 mph, with gusts as high as 25 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:
10:12 am CST Feb 19, 2026
Forecast Valid:
11am CST Feb 19, 2026-6pm CST Feb 25, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation