Hazardous Weather Conditions
Current conditions at
Decatur Airport (KDEC)
Lat: 39.83°NLon: 88.87°WElev: 670ft.
Fog/Mist
71°F
22°C
| Humidity | 94% |
| Wind Speed | S 9 mph |
| Barometer | 29.72 in (1005.8 mb) |
| Dewpoint | 69°F (21°C) |
| Visibility | 4.00 mi |
| Last update | 1 Aug 12:54 am CDT |
Extended Forecast for
Illiopolis IL
Overnight
Low: 68 °F
Chance
ShowersSaturday
High: 76 °F
Chance
Showers then
ShowersSaturday Night
Low: 67 °F
Showers then
Chance
ShowersSunday
High: 79 °F
Partly Sunny
Sunday Night
Low: 63 °F
Mostly Clear
Monday
High: 81 °F
Sunny
Monday Night
Low: 63 °F
Mostly Clear
Tuesday
High: 83 °F
Sunny
Tuesday Night
Low: 65 °F
Mostly Clear
Detailed Forecast
Overnight
A 40 percent chance of showers and thunderstorms. Cloudy, with a low around 68. South wind 8 to 13 mph, with gusts as high as 24 mph.
Saturday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2pm. High near 76. Light and variable wind becoming north northwest 5 to 10 mph in the afternoon. Winds could gust as high as 15 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Saturday Night
Showers and thunderstorms before 1am, then a chance of showers. Low around 67. North wind 15 to 17 mph, with gusts as high as 28 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Sunday
Partly sunny, with a high near 79. North wind around 17 mph, with gusts as high as 26 mph.
Sunday Night
Mostly clear, with a low around 63. North wind 6 to 13 mph, with gusts as high as 21 mph.
Monday
Sunny, with a high near 81. North northeast wind 6 to 9 mph.
Monday Night
Mostly clear, with a low around 63. Northeast wind 5 to 7 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 83.
Tuesday Night
Mostly clear, with a low around 65.
Wednesday
Sunny, with a high near 84.
Wednesday Night
A chance of showers. Partly cloudy, with a low around 67.
Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 84.
Thursday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 69.
Friday
A chance of showers and thunderstorms. Mostly sunny, with a high near 86.
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)
1:26 am CDT Aug 1, 2026
1am CDT Aug 1, 2026-6pm CDT Aug 7, 2026
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