Current conditions at
Decatur Airport (KDEC)
Lat: 39.83°NLon: 88.87°WElev: 670ft.
Fair
61°F
16°C
| Humidity | 90% |
| Wind Speed | Calm |
| Barometer | 30.11 in (1019.3 mb) |
| Dewpoint | 58°F (14°C) |
| Visibility | 10.00 mi |
| Last update | 28 Aug 4:54 am CDT |
Extended Forecast for
Illiopolis IL
Today
High: 84 °F
Patchy Fog
then Mostly
SunnyTonight
Low: 61 °F
Mostly Clear
Saturday
High: 86 °F
Mostly Sunny
Saturday Night
Low: 67 °F
Partly Cloudy
Sunday
High: 91 °F
Mostly Sunny
Sunday Night
Low: 73 °F
Mostly Clear
Monday
High: 95 °F
Hot
Monday Night
Low: 75 °F
Mostly Clear
Tuesday
High: 98 °F
Hot
Detailed Forecast
Today
Patchy fog before 8am. Otherwise, sunny, with a high near 84. Light north northeast wind.
Tonight
Mostly clear, with a low around 61. Light and variable wind becoming southeast around 5 mph.
Saturday
Mostly sunny, with a high near 86. South wind 5 to 8 mph.
Saturday Night
Partly cloudy, with a low around 67. South southeast wind 7 to 9 mph, with gusts as high as 16 mph.
Sunday
Mostly sunny, with a high near 91. South wind 11 to 16 mph, with gusts as high as 20 mph.
Sunday Night
Mostly clear, with a low around 73. South wind around 11 mph, with gusts as high as 18 mph.
Monday
Sunny and hot, with a high near 95. South southwest wind 11 to 14 mph, with gusts as high as 18 mph.
Monday Night
Mostly clear, with a low around 75.
Tuesday
Sunny and hot, with a high near 98.
Tuesday Night
Mostly clear, with a low around 76.
Wednesday
Sunny and hot, with a high near 98.
Wednesday Night
Mostly clear, with a low around 75.
Thursday
Sunny and hot, with a high near 98.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Illiopolis IL
39.85°N 89.26°W (Elev. 607 ft)
39.85°N 89.26°W (Elev. 607 ft)
4:36 am CDT Aug 28, 2026
5am CDT Aug 28, 2026-6pm CDT Sep 3, 2026
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