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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

73°F

23°C

Humidity 94%
Wind Speed SW 12 mph
Barometer 29.86 in (1010.7 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 15 Oct 6:54 pm CDT
Extended Forecast for

Assumption IL

  • Tonight

    Tonight: A chance of showers and thunderstorms before 1am, then a slight chance of showers between 1am and 2am. Mostly cloudy, with a low around 45. Southwest wind 10 to 18 mph becoming northwest after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 40%.

    Low: 45 °F

    Chance
    Showers

  • Friday

    Friday: A 30 percent chance of showers after 4pm. Partly sunny, with a high near 55. Breezy, with a northwest wind 18 to 20 mph, with gusts as high as 31 mph.

    High: 55 °F

    Breezy.
    Partly Sunny
    then Chance
    Showers

  • Friday Night

    Friday Night: Partly cloudy, with a low around 35. North wind 9 to 15 mph, with gusts as high as 25 mph.

    Low: 35 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 59. North wind around 6 mph becoming calm in the afternoon.

    High: 59 °F

    Sunny

  • Saturday Night

    Saturday Night: Areas of frost after 3am. Otherwise, clear, with a low around 34. Light and variable wind.

    Low: 34 °F

    Clear then
    Areas Frost

  • Sunday

    Sunday: Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 68. South wind 3 to 7 mph.

    High: 68 °F

    Frost then
    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 37. Light south southeast wind.

    Low: 37 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 71.

    High: 71 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 41.

    Low: 41 °F

    Partly Cloudy

Detailed Forecast

Tonight
A chance of showers and thunderstorms before 1am, then a slight chance of showers between 1am and 2am. Mostly cloudy, with a low around 45. Southwest wind 10 to 18 mph becoming northwest after midnight. Winds could gust as high as 31 mph. Chance of precipitation is 40%.
Friday
A 30 percent chance of showers after 4pm. Partly sunny, with a high near 55. Breezy, with a northwest wind 18 to 20 mph, with gusts as high as 31 mph.
Friday Night
Partly cloudy, with a low around 35. North wind 9 to 15 mph, with gusts as high as 25 mph.
Saturday
Sunny, with a high near 59. North wind around 6 mph becoming calm in the afternoon.
Saturday Night
Areas of frost after 3am. Otherwise, clear, with a low around 34. Light and variable wind.
Sunday
Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 68. South wind 3 to 7 mph.
Sunday Night
Mostly clear, with a low around 37. Light south southeast wind.
Monday
Mostly sunny, with a high near 71.
Monday Night
Partly cloudy, with a low around 41.
Tuesday
Mostly sunny, with a high near 76.
Tuesday Night
Mostly clear, with a low around 45.
Wednesday
Sunny, with a high near 79.
Wednesday Night
Mostly clear, with a low around 47.
Thursday
Sunny, with a high near 80.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Assumption IL
 39.51°N 89.05°W (Elev. 636 ft)
Last Update:
6:51 pm CDT Oct 15, 2026
Forecast Valid:
7pm CDT Oct 15, 2026-6pm CDT Oct 22, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation