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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Overcast

28°F

-2°C

Humidity 56%
Wind Speed SW 5 mph
Barometer 30.10 in (1019.5 mb)
Dewpoint 14°F (-10°C)
Visibility 10.00 mi
Wind Chill22°F (-6°C)
Last update 17 Jan 8:52 am CST
Extended Forecast for

Saint Johns IL

  • Today

    Today: Snow showers likely, mainly before noon, then a chance of flurries after 1pm. Partly sunny, with a high near 30. Southwest wind 7 to 17 mph becoming west northwest in the morning. Winds could gust as high as 25 mph. Chance of precipitation is 60%. Total daytime snow accumulation of less than a half inch possible.

    High: 30 °F

    Snow Showers
    Likely then
    Slight Chance
    Snow Showers

  • Tonight

    Tonight: Mostly clear, with a low around 13. West northwest wind 6 to 11 mph, with gusts as high as 21 mph.

    Low: 13 °F

    Mostly Clear

  • Sunday

    Sunday: Increasing clouds, with a high near 32. South southwest wind 5 to 14 mph, with gusts as high as 21 mph.

    High: 32 °F

    Increasing
    Clouds

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 15. South southwest wind 10 to 14 mph becoming northwest after midnight. Winds could gust as high as 23 mph.

    Low: 15 °F

    Partly Cloudy

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 23. Northwest wind 7 to 14 mph, with gusts as high as 23 mph.

    High: 23 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 11. Northwest wind around 5 mph becoming calm.

    Low: 11 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 36. South southwest wind 5 to 13 mph, with gusts as high as 20 mph.

    High: 36 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 28. South wind 11 to 15 mph, with gusts as high as 25 mph.

    Low: 28 °F

    Mostly Clear

  • Wednesday

    Wednesday: Partly sunny, with a high near 46. South southwest wind 8 to 14 mph, with gusts as high as 24 mph.

    High: 46 °F

    Partly Sunny

Detailed Forecast

Today
Snow showers likely, mainly before noon, then a chance of flurries after 1pm. Partly sunny, with a high near 30. Southwest wind 7 to 17 mph becoming west northwest in the morning. Winds could gust as high as 25 mph. Chance of precipitation is 60%. Total daytime snow accumulation of less than a half inch possible.
Tonight
Mostly clear, with a low around 13. West northwest wind 6 to 11 mph, with gusts as high as 21 mph.
Sunday
Increasing clouds, with a high near 32. South southwest wind 5 to 14 mph, with gusts as high as 21 mph.
Sunday Night
Partly cloudy, with a low around 15. South southwest wind 10 to 14 mph becoming northwest after midnight. Winds could gust as high as 23 mph.
M.L.King Day
Mostly sunny, with a high near 23. Northwest wind 7 to 14 mph, with gusts as high as 23 mph.
Monday Night
Mostly clear, with a low around 11. Northwest wind around 5 mph becoming calm.
Tuesday
Sunny, with a high near 36. South southwest wind 5 to 13 mph, with gusts as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 28. South wind 11 to 15 mph, with gusts as high as 25 mph.
Wednesday
Partly sunny, with a high near 46. South southwest wind 8 to 14 mph, with gusts as high as 24 mph.
Wednesday Night
A slight chance of rain showers before midnight, then a slight chance of snow showers. Partly cloudy, with a low around 22. West southwest wind around 7 mph becoming north after midnight.
Thursday
A slight chance of snow showers. Mostly sunny, with a high near 35. North northwest wind 6 to 8 mph.
Thursday Night
A slight chance of snow showers. Partly cloudy, with a low around 19. North wind around 6 mph becoming southeast after midnight.
Friday
A slight chance of rain and snow showers. Mostly sunny, with a high near 36. Southeast wind 6 to 9 mph becoming southwest in the afternoon.
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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:
8:07 am CST Jan 17, 2026
Forecast Valid:
9am CST Jan 17, 2026-6pm CST Jan 23, 2026
 
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