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Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

50°F

10°C

Humidity 89%
Wind Speed E 5 mph
Barometer 30.13 in (1020.2 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Wind Chill48°F (9°C)
Last update 10 Oct 7:54 am CDT
Extended Forecast for

Assumption IL

  • Today

    Today: Mostly cloudy, with a high near 80. Southeast wind 6 to 8 mph.

    High: 80 °F

    Mostly Cloudy

  • Tonight

    Tonight: Mostly cloudy, with a low around 55. East southeast wind around 6 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 60. Calm wind becoming south southwest around 6 mph after midnight.

    Low: 60 °F

    Mostly Clear

  • Columbus Day

    Columbus Day: Sunny, with a high near 90. Southwest wind 6 to 13 mph, with gusts as high as 17 mph.

    High: 90 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 68. South southwest wind 6 to 9 mph, with gusts as high as 16 mph.

    Low: 68 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 87. West northwest wind around 10 mph, with gusts as high as 16 mph.

    High: 87 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers after 1am. Mostly clear, with a low around 59.

    Low: 59 °F

    Mostly Clear
    then Chance
    Showers

  • Wednesday

    Wednesday: Showers likely. Mostly sunny, with a high near 77. Chance of precipitation is 60%.

    High: 77 °F

    Showers
    Likely

Detailed Forecast

Today
Mostly cloudy, with a high near 80. Southeast wind 6 to 8 mph.
Tonight
Mostly cloudy, with a low around 55. East southeast wind around 6 mph becoming calm after midnight.
Sunday
Sunny, with a high near 84. Light and variable wind.
Sunday Night
Mostly clear, with a low around 60. Calm wind becoming south southwest around 6 mph after midnight.
Columbus Day
Sunny, with a high near 90. Southwest wind 6 to 13 mph, with gusts as high as 17 mph.
Monday Night
Mostly clear, with a low around 68. South southwest wind 6 to 9 mph, with gusts as high as 16 mph.
Tuesday
Sunny, with a high near 87. West northwest wind around 10 mph, with gusts as high as 16 mph.
Tuesday Night
A 30 percent chance of showers after 1am. Mostly clear, with a low around 59.
Wednesday
Showers likely. Mostly sunny, with a high near 77. Chance of precipitation is 60%.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 56.
Thursday
A chance of showers. Mostly cloudy, with a high near 76.
Thursday Night
A chance of showers. Mostly cloudy, with a low around 51.
Friday
Mostly sunny, with a high near 68.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Assumption IL
 39.51°N 89.05°W (Elev. 636 ft)
Last Update:
7:35 am CDT Oct 10, 2026
Forecast Valid:
7am 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