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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

74°F

23°C

Humidity 85%
Wind Speed N 7 mph
Barometer 29.97 in (1014.3 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Last update 13 Aug 9:54 pm CDT
Extended Forecast for

Harristown IL

  • Tonight

    Tonight: Patchy fog after 4am. Otherwise, mostly clear, with a low around 64. Light north northeast wind.

    Low: 64 °F

    Mostly Clear
    then Patchy
    Fog

  • Thursday

    Thursday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 85. East northeast wind 3 to 5 mph.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 67. Light east northeast wind.

    Low: 67 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 90. South wind around 6 mph.

    High: 90 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 71. South southeast wind 3 to 5 mph.

    Low: 71 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 93. South southwest wind around 6 mph.

    High: 93 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 73. South wind 3 to 5 mph.

    Low: 73 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 93.

    High: 93 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 72.

    Low: 72 °F

    Partly Cloudy

Detailed Forecast

Tonight
Patchy fog after 4am. Otherwise, mostly clear, with a low around 64. Light north northeast wind.
Thursday
Patchy fog before 8am. Otherwise, mostly sunny, with a high near 85. East northeast wind 3 to 5 mph.
Thursday Night
Mostly clear, with a low around 67. Light east northeast wind.
Friday
Sunny, with a high near 90. South wind around 6 mph.
Friday Night
Mostly clear, with a low around 71. South southeast wind 3 to 5 mph.
Saturday
Sunny, with a high near 93. South southwest wind around 6 mph.
Saturday Night
Mostly clear, with a low around 73. South wind 3 to 5 mph.
Sunday
Sunny, with a high near 93.
Sunday Night
Partly cloudy, with a low around 72.
Monday
Mostly sunny, with a high near 92.
Monday Night
Mostly clear, with a low around 71.
Tuesday
A chance of showers and thunderstorms. Mostly sunny, with a high near 89.
Tuesday Night
A chance of showers. Partly cloudy, with a low around 66.
Wednesday
Mostly sunny, with a high near 83.
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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:
9:41 pm CDT Aug 13, 2025
Forecast Valid:
10pm CDT Aug 13, 2025-6pm CDT Aug 20, 2025
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation