National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Mostly Cloudy

64°F

18°C

Humidity 87%
Wind Speed S 18 G 24 mph
Barometer 29.80 in (1008.8 mb)
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Last update 9 Mar 9:54 pm CDT
Extended Forecast for

Decatur IL

  • Tonight

    Tonight: Partly cloudy, with a low around 60. South southwest wind 10 to 14 mph, with gusts as high as 25 mph.

    Low: 60 °F

    Partly Cloudy

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 78. South southwest wind 9 to 15 mph, with gusts as high as 26 mph.

    High: 78 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 11pm. Low around 51. South southwest wind 14 to 16 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 51 °F

    T-storms

  • Wednesday

    Wednesday: Showers and possibly a thunderstorm. Temperature rising to near 61 by 10am, then falling to around 45 during the remainder of the day. Southwest wind 15 to 18 mph becoming northwest in the afternoon. Winds could gust as high as 30 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.

    High: 61 °F⇓

    Showers

  • Wednesday Night

    Wednesday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 30. Northwest wind 8 to 17 mph, with gusts as high as 26 mph.

    Low: 30 °F

    Decreasing
    Clouds

  • Thursday

    Thursday: Increasing clouds, with a high near 48. Northwest wind 6 to 10 mph becoming southwest in the afternoon. Winds could gust as high as 16 mph.

    High: 48 °F

    Increasing
    Clouds

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 41. Breezy, with a south wind 10 to 15 mph increasing to 16 to 21 mph after midnight. Winds could gust as high as 32 mph.

    Low: 41 °F

    Mostly Cloudy
    then Mostly
    Cloudy and
    Breezy

  • Friday

    Friday: Mostly cloudy, with a high near 56.

    High: 56 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 36.

    Low: 36 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Partly cloudy, with a low around 60. South southwest wind 10 to 14 mph, with gusts as high as 25 mph.
Tuesday
A 20 percent chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 78. South southwest wind 9 to 15 mph, with gusts as high as 26 mph.
Tuesday Night
Showers and thunderstorms likely, then showers and possibly a thunderstorm after 11pm. Low around 51. South southwest wind 14 to 16 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Wednesday
Showers and possibly a thunderstorm. Temperature rising to near 61 by 10am, then falling to around 45 during the remainder of the day. Southwest wind 15 to 18 mph becoming northwest in the afternoon. Winds could gust as high as 30 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.
Wednesday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 30. Northwest wind 8 to 17 mph, with gusts as high as 26 mph.
Thursday
Increasing clouds, with a high near 48. Northwest wind 6 to 10 mph becoming southwest in the afternoon. Winds could gust as high as 16 mph.
Thursday Night
Mostly cloudy, with a low around 41. Breezy, with a south wind 10 to 15 mph increasing to 16 to 21 mph after midnight. Winds could gust as high as 32 mph.
Friday
Mostly cloudy, with a high near 56.
Friday Night
Mostly cloudy, with a low around 36.
Saturday
Mostly cloudy, with a high near 61.
Saturday Night
A chance of rain. Mostly cloudy, with a low around 47.
Sunday
Rain likely. Mostly cloudy, with a high near 59. Breezy.
Sunday Night
A chance of rain and snow. Mostly cloudy, with a low around 25. Blustery.
Monday
Partly sunny, with a high near 36.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Decatur IL
 39.84°N 88.94°W (Elev. 692 ft)
Last Update:
9:36 pm CDT Mar 9, 2026
Forecast Valid:
10pm CDT Mar 9, 2026-6pm CDT Mar 16, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation