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.

Fair

48°F

9°C

Humidity 66%
Wind Speed Calm
Barometer 30.04 in (1017.7 mb)
Dewpoint 37°F (3°C)
Visibility 10.00 mi
Last update 18 Mar 7:54 pm CDT
Extended Forecast for

Decatur IL

  • Tonight

    Tonight: Mostly cloudy, with a low around 38. Light and variable wind.

    Low: 38 °F

    Mostly Cloudy

  • Thursday

    Thursday: Partly sunny, then gradually becoming sunny, with a high near 67. South southeast wind around 6 mph becoming east in the afternoon.

    High: 67 °F

    Becoming
    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 45. East northeast wind around 5 mph becoming light and variable.

    Low: 45 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 74. West southwest wind 6 to 11 mph, with gusts as high as 18 mph.

    High: 74 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 47. West wind 5 to 7 mph becoming north northwest after midnight.

    Low: 47 °F

    Mostly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 74. North northwest wind 5 to 8 mph becoming west southwest in the afternoon.

    High: 74 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 54. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.

    Low: 54 °F

    Mostly Clear

  • Sunday

    Sunday: Partly sunny, with a high near 73.

    High: 73 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 34.

    Low: 34 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 38. Light and variable wind.
Thursday
Partly sunny, then gradually becoming sunny, with a high near 67. South southeast wind around 6 mph becoming east in the afternoon.
Thursday Night
Partly cloudy, with a low around 45. East northeast wind around 5 mph becoming light and variable.
Friday
Mostly sunny, with a high near 74. West southwest wind 6 to 11 mph, with gusts as high as 18 mph.
Friday Night
Mostly cloudy, with a low around 47. West wind 5 to 7 mph becoming north northwest after midnight.
Saturday
Mostly sunny, with a high near 74. North northwest wind 5 to 8 mph becoming west southwest in the afternoon.
Saturday Night
Mostly clear, with a low around 54. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.
Sunday
Partly sunny, with a high near 73.
Sunday Night
Mostly cloudy, with a low around 34.
Monday
Partly sunny, with a high near 49.
Monday Night
Mostly cloudy, with a low around 31.
Tuesday
Partly sunny, with a high near 55.
Tuesday Night
Mostly cloudy, with a low around 40.
Wednesday
Mostly cloudy, with a high near 64.
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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:
7:36 pm CDT Mar 18, 2026
Forecast Valid:
8pm CDT Mar 18, 2026-6pm CDT Mar 25, 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

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation