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Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

58°F

14°C

Humidity 72%
Wind Speed Calm
Barometer 30.00 in (1015.6 mb)
Dewpoint 49°F (9°C)
Visibility 9.00 mi
Last update 8 Oct 1:54 am CDT
Extended Forecast for

Assumption IL

  • Overnight

    Overnight: Clear, with a low around 53. Light northwest wind.

    Low: 53 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 82. Calm wind becoming west around 5 mph in the afternoon.

    High: 82 °F

    Sunny

  • Thursday Night

    Thursday Night: Clear, with a low around 53. Calm wind becoming southeast around 5 mph after midnight.

    Low: 53 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 86. South wind 6 to 11 mph, with gusts as high as 17 mph.

    High: 86 °F

    Sunny

  • Friday Night

    Friday Night: Clear, with a low around 58. South southeast wind around 7 mph.

    Low: 58 °F

    Clear

  • Saturday

    Saturday: Increasing clouds, with a high near 84. South wind 7 to 10 mph, with gusts as high as 16 mph.

    High: 84 °F

    Increasing
    Clouds

  • Saturday Night

    Saturday Night: Showers likely, mainly after 1am. Mostly cloudy, with a low around 58. East southeast wind 6 to 8 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 58 °F

    Showers
    Likely

  • Sunday

    Sunday: A 40 percent chance of showers before 1pm. Partly sunny, with a high near 75.

    High: 75 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 56.

    Low: 56 °F

    Partly Cloudy

Detailed Forecast

Overnight
Clear, with a low around 53. Light northwest wind.
Thursday
Sunny, with a high near 82. Calm wind becoming west around 5 mph in the afternoon.
Thursday Night
Clear, with a low around 53. Calm wind becoming southeast around 5 mph after midnight.
Friday
Sunny, with a high near 86. South wind 6 to 11 mph, with gusts as high as 17 mph.
Friday Night
Clear, with a low around 58. South southeast wind around 7 mph.
Saturday
Increasing clouds, with a high near 84. South wind 7 to 10 mph, with gusts as high as 16 mph.
Saturday Night
Showers likely, mainly after 1am. Mostly cloudy, with a low around 58. East southeast wind 6 to 8 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Sunday
A 40 percent chance of showers before 1pm. Partly sunny, with a high near 75.
Sunday Night
Partly cloudy, with a low around 56.
Columbus Day
Sunny, with a high near 87.
Monday Night
Mostly clear, with a low around 59.
Tuesday
Sunny, with a high near 76.
Tuesday Night
Mostly clear, with a low around 48.
Wednesday
Sunny, with a high near 73.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Assumption IL
 39.51°N 89.07°W (Elev. 627 ft)
Last Update:
2:06 am CDT Oct 8, 2026
Forecast Valid:
2am CDT Oct 8, 2026-6pm CDT Oct 14, 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