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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

31°F

-1°C

Humidity 82%
Wind Speed W 6 mph
Barometer 30.25 in (1025.0 mb)
Dewpoint 26°F (-3°C)
Visibility 10.00 mi
Wind Chill25°F (-4°C)
Last update 12 Mar 6:54 am CDT
Extended Forecast for

Illiopolis IL

Wind Advisory March 12, 10:00pm until March 13, 01:00pm
Click here for hazard details and duration
Wind Advisory

  • Today

    Today: Sunny, with a high near 51. West wind 6 to 14 mph, with gusts as high as 20 mph.

    High: 51 °F

    Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 42. Breezy, with a south wind 15 to 20 mph increasing to 23 to 28 mph after midnight. Winds could gust as high as 40 mph.

    Low: 42 °F

    Mostly Cloudy
    and Breezy

  • Friday

    Friday: Mostly sunny, with a high near 54. Breezy, with a west northwest wind 20 to 24 mph, with gusts as high as 40 mph.

    High: 54 °F

    Mostly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 33. Northwest wind 6 to 10 mph becoming northeast after midnight. Winds could gust as high as 21 mph.

    Low: 33 °F

    Mostly Cloudy

  • Saturday

    Saturday: Mostly cloudy, with a high near 55. East southeast wind 8 to 14 mph, with gusts as high as 20 mph.

    High: 55 °F

    Mostly Cloudy

  • Saturday Night

    Saturday Night: Cloudy, with a low around 48. East southeast wind 11 to 17 mph, with gusts as high as 26 mph.

    Low: 48 °F

    Cloudy

  • Sunday

    Sunday: Rain. High near 63. Breezy, with a south wind 18 to 26 mph, with gusts as high as 37 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    High: 63 °F

    Breezy. Rain
    Likely then
    Rain

  • Sunday Night

    Sunday Night: Rain and snow likely before 1am, then a chance of snow. Cloudy, with a low around 20. Windy. Chance of precipitation is 70%.

    Low: 20 °F

    Rain/Snow
    Likely and
    Windy

  • Monday

    Monday: Mostly cloudy, with a high near 27. Blustery.

    High: 27 °F

    Mostly Cloudy
    and Blustery

Detailed Forecast

Today
Sunny, with a high near 51. West wind 6 to 14 mph, with gusts as high as 20 mph.
Tonight
Mostly cloudy, with a low around 42. Breezy, with a south wind 15 to 20 mph increasing to 23 to 28 mph after midnight. Winds could gust as high as 40 mph.
Friday
Mostly sunny, with a high near 54. Breezy, with a west northwest wind 20 to 24 mph, with gusts as high as 40 mph.
Friday Night
Mostly cloudy, with a low around 33. Northwest wind 6 to 10 mph becoming northeast after midnight. Winds could gust as high as 21 mph.
Saturday
Mostly cloudy, with a high near 55. East southeast wind 8 to 14 mph, with gusts as high as 20 mph.
Saturday Night
Cloudy, with a low around 48. East southeast wind 11 to 17 mph, with gusts as high as 26 mph.
Sunday
Rain. High near 63. Breezy, with a south wind 18 to 26 mph, with gusts as high as 37 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Sunday Night
Rain and snow likely before 1am, then a chance of snow. Cloudy, with a low around 20. Windy. Chance of precipitation is 70%.
Monday
Mostly cloudy, with a high near 27. Blustery.
Monday Night
Partly cloudy, with a low around 11.
Tuesday
Mostly sunny, with a high near 32.
Tuesday Night
Mostly cloudy, with a low around 24.
Wednesday
Partly sunny, with a high near 49.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Illiopolis IL
 39.85°N 89.26°W (Elev. 607 ft)
Last Update:
6:37 am CDT Mar 12, 2026
Forecast Valid:
7am CDT Mar 12, 2026-6pm CDT Mar 18, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation