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

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

81°F

27°C

Humidity 53%
Wind Speed SW 15 mph
Barometer 29.97 in (1014.2 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 12 Oct 10:54 am CDT
Extended Forecast for

Decatur IL

  • Columbus Day

    Columbus Day: Sunny, with a high near 90. Southwest wind 11 to 15 mph, with gusts as high as 23 mph.

    High: 90 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 71. South southwest wind 9 to 13 mph, with gusts as high as 18 mph.

    Low: 71 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 92. Southwest wind 10 to 13 mph, with gusts as high as 18 mph.

    High: 92 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Showers likely and possibly a thunderstorm after 1am. Increasing clouds, with a low around 70. South southwest wind around 6 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 70 °F

    Mostly Clear
    then Showers
    Likely

  • Wednesday

    Wednesday: Showers. High near 80. West northwest wind 5 to 7 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.

    High: 80 °F

    Showers

  • Wednesday Night

    Wednesday Night: Showers likely, mainly after 1am. Mostly cloudy, with a low around 61. East northeast wind around 8 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 61 °F

    Showers
    Likely

  • Thursday

    Thursday: Showers, with thunderstorms also possible after 1pm. High near 77. East wind 8 to 11 mph becoming southwest in the afternoon. Winds could gust as high as 15 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    High: 77 °F

    Showers

  • Thursday Night

    Thursday Night: A 40 percent chance of showers before 1am. Mostly cloudy, with a low around 50. Breezy.

    Low: 50 °F

    Chance
    Showers and
    Breezy

  • Friday

    Friday: Mostly sunny, with a high near 61. Breezy.

    High: 61 °F

    Mostly Sunny
    and Breezy

Detailed Forecast

Columbus Day
Sunny, with a high near 90. Southwest wind 11 to 15 mph, with gusts as high as 23 mph.
Tonight
Mostly clear, with a low around 71. South southwest wind 9 to 13 mph, with gusts as high as 18 mph.
Tuesday
Sunny, with a high near 92. Southwest wind 10 to 13 mph, with gusts as high as 18 mph.
Tuesday Night
Showers likely and possibly a thunderstorm after 1am. Increasing clouds, with a low around 70. South southwest wind around 6 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday
Showers. High near 80. West northwest wind 5 to 7 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.
Wednesday Night
Showers likely, mainly after 1am. Mostly cloudy, with a low around 61. East northeast wind around 8 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Thursday
Showers, with thunderstorms also possible after 1pm. High near 77. East wind 8 to 11 mph becoming southwest in the afternoon. Winds could gust as high as 15 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Thursday Night
A 40 percent chance of showers before 1am. Mostly cloudy, with a low around 50. Breezy.
Friday
Mostly sunny, with a high near 61. Breezy.
Friday Night
Mostly clear, with a low around 36.
Saturday
Sunny, with a high near 60.
Saturday Night
Clear, with a low around 36.
Sunday
Sunny, with a high near 67.
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 88.91°W (Elev. 620 ft)
Last Update:
11:51 am CDT Oct 12, 2026
Forecast Valid:
11am CDT Oct 12, 2026-6pm CDT Oct 18, 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