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

58°F

14°C

Humidity 41%
Wind Speed S 9 mph
Barometer 30.20 in (1023.1 mb)
Dewpoint 34°F (1°C)
Visibility 10.00 mi
Last update 20 Apr 6:54 pm CDT
Extended Forecast for

Decatur IL

  • Tonight

    Tonight: Increasing clouds, with a low around 48. South wind 6 to 11 mph, with gusts as high as 20 mph.

    Low: 48 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Mostly sunny, with a high near 78. Southwest wind 10 to 18 mph, with gusts as high as 32 mph.

    High: 78 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 58. Southwest wind 10 to 14 mph, with gusts as high as 23 mph.

    Low: 58 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: Mostly sunny, with a high near 77. West southwest wind 8 to 10 mph, with gusts as high as 16 mph.

    High: 77 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 57. South wind around 8 mph.

    Low: 57 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 80. South wind 9 to 18 mph, with gusts as high as 29 mph.

    High: 80 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 62. South wind around 17 mph, with gusts as high as 26 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 62 °F

    Partly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers and possibly a thunderstorm. High near 74. Chance of precipitation is 80%.

    High: 74 °F

    Showers

  • Friday Night

    Friday Night: A 50 percent chance of showers. Mostly cloudy, with a low around 52.

    Low: 52 °F

    Chance
    Showers

Detailed Forecast

Tonight
Increasing clouds, with a low around 48. South wind 6 to 11 mph, with gusts as high as 20 mph.
Tuesday
Mostly sunny, with a high near 78. Southwest wind 10 to 18 mph, with gusts as high as 32 mph.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 58. Southwest wind 10 to 14 mph, with gusts as high as 23 mph.
Wednesday
Mostly sunny, with a high near 77. West southwest wind 8 to 10 mph, with gusts as high as 16 mph.
Wednesday Night
Mostly clear, with a low around 57. South wind around 8 mph.
Thursday
Mostly sunny, with a high near 80. South wind 9 to 18 mph, with gusts as high as 29 mph.
Thursday Night
Showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 62. South wind around 17 mph, with gusts as high as 26 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday
Showers and possibly a thunderstorm. High near 74. Chance of precipitation is 80%.
Friday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 52.
Saturday
Mostly sunny, with a high near 70.
Saturday Night
Mostly cloudy, with a low around 49.
Sunday
Partly sunny, with a high near 70.
Sunday Night
A chance of showers. Mostly cloudy, with a low around 51.
Monday
A chance of showers. Mostly cloudy, with a high near 70.
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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:
6:36 pm CDT Apr 20, 2026
Forecast Valid:
7pm CDT Apr 20, 2026-6pm CDT Apr 27, 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