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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Partly Cloudy and Breezy

80°F

27°C

Humidity 60%
Wind Speed S 24 G 33 mph
Barometer 29.82 in (1009.2 mb)
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 17 Apr 2:54 pm CDT
Extended Forecast for

2 Miles ENE Harristown IL

Flood Watch April 17, 06:00pm until April 18, 04:00am
Click here for hazard details and duration
Flood Watch

  • This Afternoon

    This Afternoon: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 83. Breezy, with a south wind around 22 mph, with gusts as high as 32 mph.

    High: 83 °F

    Slight Chance
    T-storms and
    Breezy

  • Tonight

    Tonight: Showers and thunderstorms. Low around 46. South wind around 18 mph becoming west southwest in the evening. Winds could gust as high as 31 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

    Low: 46 °F

    Showers

  • Saturday

    Saturday: A 30 percent chance of showers, mainly before 8am. Mostly cloudy, then gradually becoming sunny, with a high near 55. Breezy, with a northwest wind 18 to 21 mph, with gusts as high as 29 mph.

    High: 55 °F

    Breezy.
    Chance
    Showers then
    Sunny

  • Saturday Night

    Saturday Night: Patchy frost after 2am. Otherwise, mostly clear, with a low around 36. Northwest wind 7 to 16 mph becoming west southwest after midnight. Winds could gust as high as 24 mph.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Frost

  • Sunday

    Sunday: Patchy frost before 9am. Otherwise, sunny, with a high near 60. Southwest wind 7 to 12 mph becoming west 13 to 18 mph in the afternoon. Winds could gust as high as 28 mph.

    High: 60 °F

    Patchy Frost
    then Mostly
    Sunny

  • Sunday Night

    Sunday Night: Patchy frost after 2am. Otherwise, mostly clear, with a low around 36. North northwest wind 6 to 11 mph becoming northeast after midnight. Winds could gust as high as 18 mph.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Frost

  • Monday

    Monday: Patchy frost before 9am. Otherwise, sunny, with a high near 61. East wind 6 to 9 mph becoming south in the afternoon.

    High: 61 °F

    Patchy Frost
    then Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 49.

    Low: 49 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 77. Breezy.

    High: 77 °F

    Mostly Sunny
    then Mostly
    Sunny and
    Breezy

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 83. Breezy, with a south wind around 22 mph, with gusts as high as 32 mph.
Tonight
Showers and thunderstorms. Low around 46. South wind around 18 mph becoming west southwest in the evening. Winds could gust as high as 31 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
Saturday
A 30 percent chance of showers, mainly before 8am. Mostly cloudy, then gradually becoming sunny, with a high near 55. Breezy, with a northwest wind 18 to 21 mph, with gusts as high as 29 mph.
Saturday Night
Patchy frost after 2am. Otherwise, mostly clear, with a low around 36. Northwest wind 7 to 16 mph becoming west southwest after midnight. Winds could gust as high as 24 mph.
Sunday
Patchy frost before 9am. Otherwise, sunny, with a high near 60. Southwest wind 7 to 12 mph becoming west 13 to 18 mph in the afternoon. Winds could gust as high as 28 mph.
Sunday Night
Patchy frost after 2am. Otherwise, mostly clear, with a low around 36. North northwest wind 6 to 11 mph becoming northeast after midnight. Winds could gust as high as 18 mph.
Monday
Patchy frost before 9am. Otherwise, sunny, with a high near 61. East wind 6 to 9 mph becoming south in the afternoon.
Monday Night
Mostly clear, with a low around 49.
Tuesday
Mostly sunny, with a high near 77. Breezy.
Tuesday Night
Partly cloudy, with a low around 55.
Wednesday
Sunny, with a high near 80.
Wednesday Night
Mostly clear, with a low around 58.
Thursday
Mostly sunny, with a high near 81.
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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:
1:46 pm CDT Apr 17, 2026
Forecast Valid:
3pm CDT Apr 17, 2026-6pm CDT Apr 23, 2026
 
Forecast Discussion
 
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Additional Resources

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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