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Hazardous Weather Conditions
Current conditions at
Decatur Airport (KDEC)
Lat: 39.83°NLon: 88.87°WElev: 670ft.
Overcast
74°F
23°C
| Humidity | 79% |
| Wind Speed | Vrbl 3 mph |
| Barometer | 30.03 in (1016.3 mb) |
| Dewpoint | 67°F (19°C) |
| Visibility | 10.00 mi |
| Last update | 14 Oct 10:54 am CDT |
Extended Forecast for
Illiopolis IL
Today
High: 76 °F
Chance
ShowersTonight
Low: 60 °F
Mostly Cloudy
then Chance
ShowersThursday
High: 75 °F
Showers
Thursday Night
Low: 47 °F
Showers and
BreezyFriday
High: 57 °F
Partly Sunny
and BreezyFriday Night
Low: 36 °F
Mostly Clear
then Patchy
FrostSaturday
High: 59 °F
Areas Frost
then SunnySaturday Night
Low: 37 °F
Clear
Sunday
High: 69 °F
Areas Frost
then Sunny
Detailed Forecast
Today
A 40 percent chance of showers, mainly before 5pm. Mostly cloudy, with a high near 76. North wind 5 to 7 mph.
Tonight
A slight chance of showers, then a chance of showers and thunderstorms after 4am. Mostly cloudy, with a low around 60. East northeast wind around 9 mph. Chance of precipitation is 30%.
Thursday
Showers and thunderstorms, mainly before 4pm, then showers likely and possibly a thunderstorm after 5pm. High near 75. East wind 7 to 9 mph becoming southwest in the afternoon. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday Night
Showers likely and possibly a thunderstorm before 7pm, then showers between 7pm and 1am. Low around 47. Breezy, with a west southwest wind 9 to 14 mph becoming northwest 16 to 21 mph after midnight. Winds could gust as high as 30 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday
Partly sunny, with a high near 57. Breezy, with a northwest wind 22 to 25 mph, with gusts as high as 34 mph.
Friday Night
Patchy frost after 5am. Otherwise, mostly clear, with a low around 36. North wind 5 to 15 mph, with gusts as high as 21 mph.
Saturday
Areas of frost before 8am. Otherwise, sunny, with a high near 59. Calm wind.
Saturday Night
Clear, with a low around 37.
Sunday
Areas of frost before 7am. Otherwise, sunny, with a high near 69.
Sunday Night
Partly cloudy, with a low around 44.
Monday
Partly sunny, with a high near 72.
Monday Night
Partly cloudy, with a low around 47.
Tuesday
Mostly sunny, with a high near 77.
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)
10:36 am CDT Oct 14, 2026
11am CDT Oct 14, 2026-6pm CDT Oct 20, 2026
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