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Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

78°F

26°C

Humidity 37%
Wind Speed SE 8 mph
Barometer 30.08 in (1018.1 mb)
Dewpoint 50°F (10°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 10 Oct 1:54 pm CDT
Extended Forecast for

Decatur IL

  • This Afternoon

    This Afternoon: Mostly cloudy, with a high near 81. Southeast wind around 10 mph, with gusts as high as 15 mph.

    High: 81 °F

    Mostly Cloudy

  • Tonight

    Tonight: Mostly cloudy, with a low around 55. Southeast wind 5 to 8 mph becoming calm after midnight.

    Low: 55 °F

    Mostly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 84. Light and variable wind.

    High: 84 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 62. Calm wind becoming south southwest 5 to 7 mph after midnight.

    Low: 62 °F

    Mostly Clear

  • Columbus Day

    Columbus Day: Partly sunny through mid morning, then becoming sunny, with a high near 91. Southwest wind 7 to 15 mph, with gusts as high as 20 mph.

    High: 91 °F

    Becoming
    Sunny

  • Monday Night

    Monday Night: Clear, with a low around 70. South southwest wind 9 to 13 mph, with gusts as high as 18 mph.

    Low: 70 °F

    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 90. West southwest wind 13 to 15 mph, with gusts as high as 20 mph.

    High: 90 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers after 1am. Mostly clear, with a low around 64.

    Low: 64 °F

    Clear then
    Chance
    Showers

  • Wednesday

    Wednesday: Showers likely. Partly sunny, with a high near 80. Chance of precipitation is 70%.

    High: 80 °F

    Showers
    Likely

Detailed Forecast

This Afternoon
Mostly cloudy, with a high near 81. Southeast wind around 10 mph, with gusts as high as 15 mph.
Tonight
Mostly cloudy, with a low around 55. Southeast wind 5 to 8 mph becoming calm after midnight.
Sunday
Sunny, with a high near 84. Light and variable wind.
Sunday Night
Mostly clear, with a low around 62. Calm wind becoming south southwest 5 to 7 mph after midnight.
Columbus Day
Partly sunny through mid morning, then becoming sunny, with a high near 91. Southwest wind 7 to 15 mph, with gusts as high as 20 mph.
Monday Night
Clear, with a low around 70. South southwest wind 9 to 13 mph, with gusts as high as 18 mph.
Tuesday
Sunny, with a high near 90. West southwest wind 13 to 15 mph, with gusts as high as 20 mph.
Tuesday Night
A 30 percent chance of showers after 1am. Mostly clear, with a low around 64.
Wednesday
Showers likely. Partly sunny, with a high near 80. Chance of precipitation is 70%.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 60.
Thursday
Showers likely. Mostly cloudy, with a high near 75.
Thursday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 53.
Friday
Partly sunny, with a high near 68. Breezy.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Decatur IL
 39.84°N 88.97°W (Elev. 676 ft)
Last Update:
1:36 pm CDT Oct 10, 2026
Forecast Valid:
2pm CDT Oct 10, 2026-6pm CDT Oct 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