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

63°F

17°C

Humidity 81%
Wind Speed SW 12 mph
Barometer 29.94 in (1013.3 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Last update 17 Apr 12:54 am CDT
Extended Forecast for

Blue Mound IL

  • Overnight

    Overnight: Mostly clear, with a low around 56. South wind around 6 mph.

    Low: 56 °F

    Mostly Clear

  • Friday

    Friday: A 50 percent chance of showers and thunderstorms, mainly after 3pm. Partly sunny, with a high near 83. Breezy, with a south wind 9 to 14 mph increasing to 17 to 22 mph in the afternoon. Winds could gust as high as 30 mph.

    High: 83 °F

    Partly Sunny
    then Chance
    T-storms and
    Breezy

  • Friday Night

    Friday Night: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 11pm. Low around 46. South wind around 18 mph becoming west northwest after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 46 °F

    T-storms

  • Saturday

    Saturday: A 40 percent chance of showers before 1pm. Cloudy through mid morning, then gradual clearing, with a high near 55. Breezy, with a northwest wind 18 to 21 mph, with gusts as high as 28 mph.

    High: 55 °F

    Chance
    Showers and
    Breezy

  • Saturday Night

    Saturday Night: Patchy frost after 3am. Otherwise, mostly clear, with a low around 36. Northwest wind 8 to 16 mph, with gusts as high as 23 mph.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Frost

  • Sunday

    Sunday: Patchy frost before 8am. Otherwise, sunny, with a high near 60. West northwest wind 8 to 18 mph, with gusts as high as 24 mph.

    High: 60 °F

    Patchy Frost
    then Sunny

  • Sunday Night

    Sunday Night: Patchy frost after 3am. Otherwise, mostly clear, with a low around 36. North northwest wind 6 to 10 mph becoming east after midnight. Winds could gust as high as 16 mph.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Frost

  • Monday

    Monday: Patchy frost before 8am. Otherwise, sunny, with a high near 64.

    High: 64 °F

    Patchy Frost
    then Sunny

  • Monday Night

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

    Low: 49 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly clear, with a low around 56. South wind around 6 mph.
Friday
A 50 percent chance of showers and thunderstorms, mainly after 3pm. Partly sunny, with a high near 83. Breezy, with a south wind 9 to 14 mph increasing to 17 to 22 mph in the afternoon. Winds could gust as high as 30 mph.
Friday Night
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 11pm. Low around 46. South wind around 18 mph becoming west northwest after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.
Saturday
A 40 percent chance of showers before 1pm. Cloudy through mid morning, then gradual clearing, with a high near 55. Breezy, with a northwest wind 18 to 21 mph, with gusts as high as 28 mph.
Saturday Night
Patchy frost after 3am. Otherwise, mostly clear, with a low around 36. Northwest wind 8 to 16 mph, with gusts as high as 23 mph.
Sunday
Patchy frost before 8am. Otherwise, sunny, with a high near 60. West northwest wind 8 to 18 mph, with gusts as high as 24 mph.
Sunday Night
Patchy frost after 3am. Otherwise, mostly clear, with a low around 36. North northwest wind 6 to 10 mph becoming east after midnight. Winds could gust as high as 16 mph.
Monday
Patchy frost before 8am. Otherwise, sunny, with a high near 64.
Monday Night
Mostly clear, with a low around 49.
Tuesday
Mostly sunny, with a high near 76. Breezy.
Tuesday Night
Mostly clear, with a low around 55.
Wednesday
Sunny, with a high near 79.
Wednesday Night
Mostly clear, with a low around 57.
Thursday
Mostly sunny, with a high near 80.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Blue Mound IL
 39.69°N 89.12°W (Elev. 614 ft)
Last Update:
1:26 am CDT Apr 17, 2026
Forecast Valid:
1am CDT Apr 17, 2026-6pm CDT Apr 23, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation