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

59°F

15°C

Humidity 90%
Wind Speed S 5 mph
Barometer 29.94 in (1013.5 mb)
Dewpoint 56°F (13°C)
Visibility 10.00 mi
Last update 16 Apr 11:54 pm CDT
Extended Forecast for

Decatur IL

  • Tonight

    Tonight: Clear, with a low around 57. South wind 3 to 6 mph.

    Low: 57 °F

    Clear

  • Friday

    Friday: Mostly sunny, with a high near 82. South wind 7 to 17 mph, with gusts as high as 29 mph.

    High: 82 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 11pm. Low around 49. South wind around 16 mph becoming west after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 49 °F

    T-storms

  • Saturday

    Saturday: A 50 percent chance of showers before 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 58. West northwest wind 16 to 18 mph, with gusts as high as 29 mph.

    High: 58 °F

    Chance
    Showers

  • Saturday Night

    Saturday Night: Patchy frost after 3am. Otherwise, mostly clear, with a low around 37. West northwest wind 8 to 15 mph, with gusts as high as 24 mph.

    Low: 37 °F

    Mostly Clear
    then Patchy
    Frost

  • Sunday

    Sunday: Patchy frost before 8am. Otherwise, sunny, with a high near 58. West northwest wind 8 to 16 mph, with gusts as high as 26 mph.

    High: 58 °F

    Patchy Frost
    then Mostly
    Sunny

  • Sunday Night

    Sunday Night: Patchy frost after 3am. Otherwise, mostly clear, with a low around 37. North northwest wind 5 to 10 mph becoming east after midnight. Winds could gust as high as 17 mph.

    Low: 37 °F

    Mostly Clear
    then Patchy
    Frost

  • Monday

    Monday: Patchy frost before 8am. Otherwise, sunny, with a high near 65.

    High: 65 °F

    Patchy Frost
    then Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 50.

    Low: 50 °F

    Mostly Clear

Detailed Forecast

Tonight
Clear, with a low around 57. South wind 3 to 6 mph.
Friday
Mostly sunny, with a high near 82. South wind 7 to 17 mph, with gusts as high as 29 mph.
Friday Night
Showers and thunderstorms likely, then showers and possibly a thunderstorm after 11pm. Low around 49. South wind around 16 mph becoming west after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Saturday
A 50 percent chance of showers before 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 58. West northwest wind 16 to 18 mph, with gusts as high as 29 mph.
Saturday Night
Patchy frost after 3am. Otherwise, mostly clear, with a low around 37. West northwest wind 8 to 15 mph, with gusts as high as 24 mph.
Sunday
Patchy frost before 8am. Otherwise, sunny, with a high near 58. West northwest wind 8 to 16 mph, with gusts as high as 26 mph.
Sunday Night
Patchy frost after 3am. Otherwise, mostly clear, with a low around 37. North northwest wind 5 to 10 mph becoming east after midnight. Winds could gust as high as 17 mph.
Monday
Patchy frost before 8am. Otherwise, sunny, with a high near 65.
Monday Night
Mostly clear, with a low around 50.
Tuesday
Mostly sunny, with a high near 76.
Tuesday Night
Partly cloudy, with a low around 56.
Wednesday
Mostly sunny, with a high near 76.
Wednesday Night
Mostly clear, with a low around 54.
Thursday
Mostly sunny, with a high near 77.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Decatur IL
 39.84°N 88.94°W (Elev. 692 ft)
Last Update:
10:36 pm CDT Apr 16, 2026
Forecast Valid:
11pm CDT Apr 16, 2026-6pm CDT Apr 23, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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