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

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

41°F

5°C

Humidity 86%
Wind Speed W 6 mph
Barometer 29.83 in (1010.3 mb)
Dewpoint 37°F (3°C)
Visibility 10.00 mi
Wind Chill37°F (3°C)
Last update 8 Nov 5:54 am CST
Extended Forecast for

Harristown IL

  • Today

    Today: A 40 percent chance of rain, mainly after 3pm. Mostly cloudy, with a high near 57. Light and variable wind becoming east 5 to 7 mph in the morning.

    High: 57 °F

    Mostly Cloudy
    then Chance
    Rain

  • Tonight

    Tonight: Rain before 3am, then a slight chance of snow. Low around 32. Breezy, with an east wind 8 to 13 mph becoming north northwest 16 to 21 mph after midnight. Winds could gust as high as 30 mph. Chance of precipitation is 90%. Little or no snow accumulation expected.

    Low: 32 °F

    Rain then
    Chance
    Rain/Snow and
    Breezy

  • Sunday

    Sunday: A 20 percent chance of snow showers. Partly sunny, with a high near 38. Breezy, with a northwest wind 20 to 23 mph, with gusts as high as 33 mph.

    High: 38 °F

    Slight Chance
    Snow Showers
    and Breezy

  • Sunday Night

    Sunday Night: A 30 percent chance of snow showers after midnight. Partly cloudy, with a low around 22. Northwest wind 15 to 18 mph, with gusts as high as 25 mph.

    Low: 22 °F

    Partly Cloudy
    then Chance
    Snow Showers

  • Monday

    Monday: Sunny, with a high near 38. Breezy, with a northwest wind 13 to 20 mph, with gusts as high as 25 mph.

    High: 38 °F

    Sunny and
    Breezy then
    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 23. West northwest wind 7 to 11 mph becoming south southwest after midnight. Winds could gust as high as 15 mph.

    Low: 23 °F

    Partly Cloudy

  • Veterans Day

    Veterans Day: Partly sunny, with a high near 49. Breezy, with a south southwest wind 13 to 21 mph, with gusts as high as 28 mph.

    High: 49 °F

    Partly Sunny
    and Breezy

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 36.

    Low: 36 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 58.

    High: 58 °F

    Sunny

Detailed Forecast

Today
A 40 percent chance of rain, mainly after 3pm. Mostly cloudy, with a high near 57. Light and variable wind becoming east 5 to 7 mph in the morning.
Tonight
Rain before 3am, then a slight chance of snow. Low around 32. Breezy, with an east wind 8 to 13 mph becoming north northwest 16 to 21 mph after midnight. Winds could gust as high as 30 mph. Chance of precipitation is 90%. Little or no snow accumulation expected.
Sunday
A 20 percent chance of snow showers. Partly sunny, with a high near 38. Breezy, with a northwest wind 20 to 23 mph, with gusts as high as 33 mph.
Sunday Night
A 30 percent chance of snow showers after midnight. Partly cloudy, with a low around 22. Northwest wind 15 to 18 mph, with gusts as high as 25 mph.
Monday
Sunny, with a high near 38. Breezy, with a northwest wind 13 to 20 mph, with gusts as high as 25 mph.
Monday Night
Partly cloudy, with a low around 23. West northwest wind 7 to 11 mph becoming south southwest after midnight. Winds could gust as high as 15 mph.
Veterans Day
Partly sunny, with a high near 49. Breezy, with a south southwest wind 13 to 21 mph, with gusts as high as 28 mph.
Tuesday Night
Mostly clear, with a low around 36.
Wednesday
Sunny, with a high near 58.
Wednesday Night
Mostly clear, with a low around 32.
Thursday
Sunny, with a high near 57.
Thursday Night
Partly cloudy, with a low around 37.
Friday
Mostly sunny, with a high near 63.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Harristown IL
 39.84°N 89.06°W (Elev. 699 ft)
Last Update:
5:37 am CST Nov 8, 2025
Forecast Valid:
6am CST Nov 8, 2025-6pm CST Nov 14, 2025
 
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Additional Resources

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Chance of Precipitation