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

31°F

-1°C

Humidity 43%
Wind Speed S 20 G 25 mph
Barometer 30.08 in (1019.4 mb)
Dewpoint 11°F (-12°C)
Visibility 10.00 mi
Wind Chill19°F (-7°C)
Last update 21 Jan 1:54 am CST
Extended Forecast for

2 Miles ENE Harristown IL

  • Overnight

    Overnight: Mostly cloudy, with a low around 25. South southwest wind around 15 mph, with gusts as high as 24 mph.

    Low: 25 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Cloudy through mid morning, then gradual clearing, with a high near 39. West southwest wind 13 to 17 mph, with gusts as high as 26 mph.

    High: 39 °F

    Becoming
    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 19. Breezy, with a southwest wind 10 to 20 mph becoming west northwest after midnight. Winds could gust as high as 30 mph.

    Low: 19 °F

    Partly Cloudy
    and Breezy
    then Mostly
    Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 32. West wind 7 to 10 mph, with gusts as high as 15 mph.

    High: 32 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 0. West wind 6 to 11 mph becoming north northwest 13 to 18 mph after midnight. Winds could gust as high as 26 mph.

    Low: 0 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly cloudy and cold, with a high near 7. North northwest wind 13 to 18 mph, with gusts as high as 26 mph.

    High: 7 °F

    Cold

  • Friday Night

    Friday Night: Mostly cloudy, with a low around -3. North northeast wind 10 to 13 mph, with gusts as high as 18 mph.

    Low: -3 °F

    Mostly Cloudy

  • Saturday

    Saturday: A 30 percent chance of snow after noon. Mostly cloudy, with a high near 11.

    High: 11 °F

    Mostly Cloudy
    then Chance
    Snow

  • Saturday Night

    Saturday Night: A 50 percent chance of snow. Mostly cloudy, with a low around 5.

    Low: 5 °F

    Chance Snow

Detailed Forecast

Overnight
Mostly cloudy, with a low around 25. South southwest wind around 15 mph, with gusts as high as 24 mph.
Wednesday
Cloudy through mid morning, then gradual clearing, with a high near 39. West southwest wind 13 to 17 mph, with gusts as high as 26 mph.
Wednesday Night
Mostly clear, with a low around 19. Breezy, with a southwest wind 10 to 20 mph becoming west northwest after midnight. Winds could gust as high as 30 mph.
Thursday
Mostly sunny, with a high near 32. West wind 7 to 10 mph, with gusts as high as 15 mph.
Thursday Night
Mostly cloudy, with a low around 0. West wind 6 to 11 mph becoming north northwest 13 to 18 mph after midnight. Winds could gust as high as 26 mph.
Friday
Mostly cloudy and cold, with a high near 7. North northwest wind 13 to 18 mph, with gusts as high as 26 mph.
Friday Night
Mostly cloudy, with a low around -3. North northeast wind 10 to 13 mph, with gusts as high as 18 mph.
Saturday
A 30 percent chance of snow after noon. Mostly cloudy, with a high near 11.
Saturday Night
A 50 percent chance of snow. Mostly cloudy, with a low around 5.
Sunday
Partly sunny, with a high near 18.
Sunday Night
Partly cloudy, with a low around 2.
Monday
Sunny, with a high near 18.
Monday Night
Mostly clear, with a low around 6.
Tuesday
Mostly sunny, with a high near 29.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles ENE Harristown IL
 39.84°N 89.03°W (Elev. 666 ft)
Last Update:
1:36 am CST Jan 21, 2026
Forecast Valid:
2am CST Jan 21, 2026-6pm CST Jan 27, 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