Heavy to Excessive Rains in The Four Corners Region and Midwest; Heat Persists in the South-Central U.S.

Repeated rounds of showers and thunderstorms could bring a flash flooding threat across the Four Corners region and from the mid-Mississippi Valley into the lower Great Lakes. Hot temperatures and high humidity will continue to challenge daily records from the Southern Plains to the lower Mississippi Valley. Read More >

Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

A Few Clouds

85°F

29°C

Humidity 68%
Wind Speed Vrbl 3 mph
Barometer 30.27 in (1024.4 mb)
Dewpoint 73°F (23°C)
Visibility 9.00 mi
Heat Index92°F (33°C)
Last update 16 Sep 11:54 am CDT
Extended Forecast for

Decatur IL

  • This Afternoon

    This Afternoon: A 20 percent chance of showers and thunderstorms, mainly between 3pm and 4pm.  Partly sunny, with a high near 90. Light and variable wind becoming west around 6 mph.

    High: 90 °F

    Slight Chance
    T-storms

  • Tonight

    Tonight: Partly cloudy, with a low around 72. North northeast wind around 5 mph becoming light and variable.

    Low: 72 °F

    Partly Cloudy

  • Thursday

    Thursday: A 20 percent chance of showers before 9am.  Increasing clouds, with a high near 92. Light and variable wind becoming west northwest 5 to 7 mph in the morning.

    High: 92 °F

    Slight Chance
    Showers then
    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 69. North northwest wind around 6 mph becoming east northeast after midnight.

    Low: 69 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 89. East northeast wind around 7 mph.

    High: 89 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 70. East wind 8 to 10 mph becoming south southeast after midnight. Winds could gust as high as 15 mph.

    Low: 70 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 94. Southwest wind 11 to 13 mph, with gusts as high as 18 mph.

    High: 94 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Showers likely and possibly a thunderstorm.  Mostly cloudy, with a low around 69. Chance of precipitation is 60%.

    Low: 69 °F

    Showers
    Likely

  • Sunday

    Sunday: A chance of showers, with thunderstorms also possible after 1pm.  Partly sunny, with a high near 86. Chance of precipitation is 50%.

    High: 86 °F

    Chance
    Showers then
    Chance
    T-storms

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms, mainly between 3pm and 4pm. Partly sunny, with a high near 90. Light and variable wind becoming west around 6 mph.
Tonight
Partly cloudy, with a low around 72. North northeast wind around 5 mph becoming light and variable.
Thursday
A 20 percent chance of showers before 9am. Increasing clouds, with a high near 92. Light and variable wind becoming west northwest 5 to 7 mph in the morning.
Thursday Night
Partly cloudy, with a low around 69. North northwest wind around 6 mph becoming east northeast after midnight.
Friday
Mostly sunny, with a high near 89. East northeast wind around 7 mph.
Friday Night
Partly cloudy, with a low around 70. East wind 8 to 10 mph becoming south southeast after midnight. Winds could gust as high as 15 mph.
Saturday
Mostly sunny, with a high near 94. Southwest wind 11 to 13 mph, with gusts as high as 18 mph.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 69. Chance of precipitation is 60%.
Sunday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 86. Chance of precipitation is 50%.
Sunday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 65.
Monday
A chance of showers. Partly sunny, with a high near 82.
Monday Night
A chance of showers. Partly cloudy, with a low around 62.
Tuesday
Mostly sunny, with a high near 79.
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ABOUT THIS FORECAST

 
Point Forecast:
Decatur IL
 39.86°N 88.94°W (Elev. 682 ft)
12:26 pm CDT Sep 16, 2026
12pm CDT Sep 16, 2026-6pm CDT Sep 22, 2026
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database