News Headlines
Current conditions at
Decatur Airport (KDEC)
Lat: 39.83°NLon: 88.87°WElev: 670ft.
Fair
51°F
11°C
| Humidity | 92% |
| Wind Speed | Calm |
| Barometer | 30.03 in (1016.7 mb) |
| Dewpoint | 49°F (9°C) |
| Visibility | 10.00 mi |
| Last update | 11 Oct 7:54 am CDT |
Extended Forecast for
Illiopolis IL
Today
High: 84 °F
Sunny
Tonight
Low: 62 °F
Increasing
CloudsColumbus Day
High: 91 °F
Decreasing
CloudsMonday Night
Low: 71 °F
Mostly Clear
Tuesday
High: 90 °F
Sunny
Tuesday Night
Low: 66 °F
Chance
T-storms then
Showers
LikelyWednesday
High: 79 °F
Showers
LikelyWednesday Night
Low: 59 °F
Showers
LikelyThursday
High: 75 °F
Showers
Likely
Detailed Forecast
Today
Sunny, with a high near 84. Light and variable wind.
Tonight
Increasing clouds, with a low around 62. South wind 3 to 7 mph.
Columbus Day
Mostly cloudy, then gradually becoming sunny, with a high near 91. Southwest wind 7 to 15 mph, with gusts as high as 21 mph.
Monday Night
Mostly clear, with a low around 71. Southwest wind around 11 mph, with gusts as high as 18 mph.
Tuesday
Sunny, with a high near 90. West wind 10 to 13 mph, with gusts as high as 18 mph.
Tuesday Night
A chance of showers before 7pm, then a chance of showers and thunderstorms between 7pm and 1am, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 66. West northwest wind around 5 mph becoming northeast after midnight. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday
Showers likely, mainly before 1pm. Mostly cloudy, with a high near 79. Northeast wind 7 to 9 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.
Wednesday Night
Showers likely, mainly after 1am. Mostly cloudy, with a low around 59. Chance of precipitation is 60%.
Thursday
Showers likely. Mostly cloudy, with a high near 75. Chance of precipitation is 70%.
Thursday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 52. Chance of precipitation is 50%.
Friday
Partly sunny, with a high near 66. Breezy.
Friday Night
Partly cloudy, with a low around 39.
Saturday
Mostly sunny, with a high near 59.
Additional Forecasts and Information
Basemap Options
Click map to change the forecast location
Loading map...
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)
7:31 am CDT Oct 11, 2026
8am CDT Oct 11, 2026-6pm CDT Oct 17, 2026
Additional Resources
Radar & Satellite Image
Hourly Weather Forecast
