National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Dangerous Heat and Heavy Rainfall into the Weekend

Hot temperatures and high humidity are forecast to continue across the mid-Mississippi Valley into this weekend. Heat Advisories remain in effect. Heavy to excessive rainfall occurring at times through the weekend could bring areas of flooding to parts of the northern Rockies, upper Midwest, central Great Lakes, and southern New England. Read More >

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

76°F

24°C

Humidity 58%
Wind Speed SW 6 mph
Barometer 29.89 in (1011.6 mb)
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 20 Sep 4:53 am CDT
Extended Forecast for

Belleville IL

  • Today

    Today: Partly sunny, with a high near 94. West wind 3 to 7 mph.

    High: 94 °F

    Partly Sunny

  • Tonight

    Tonight: A chance of showers and thunderstorms before 10pm, then showers likely and possibly a thunderstorm between 10pm and 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 68. North wind 5 to 7 mph. Chance of precipitation is 60%.

    Low: 68 °F

    Showers
    Likely

  • Monday

    Monday: A chance of showers and thunderstorms before 10am, then a slight chance of showers between 10am and 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 81. North wind 5 to 9 mph. Chance of precipitation is 40%.

    High: 81 °F

    Chance
    Showers

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 63. North wind 6 to 10 mph.

    Low: 63 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 74. North wind 9 to 11 mph.

    High: 74 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 55.

    Low: 55 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 75.

    High: 75 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 55.

    Low: 55 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 76.

    High: 76 °F

    Mostly Sunny

Detailed Forecast

Today
Partly sunny, with a high near 94. West wind 3 to 7 mph.
Tonight
A chance of showers and thunderstorms before 10pm, then showers likely and possibly a thunderstorm between 10pm and 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 68. North wind 5 to 7 mph. Chance of precipitation is 60%.
Monday
A chance of showers and thunderstorms before 10am, then a slight chance of showers between 10am and 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 81. North wind 5 to 9 mph. Chance of precipitation is 40%.
Monday Night
Mostly cloudy, with a low around 63. North wind 6 to 10 mph.
Tuesday
Mostly cloudy, with a high near 74. North wind 9 to 11 mph.
Tuesday Night
Mostly cloudy, with a low around 55.
Wednesday
Mostly sunny, with a high near 75.
Wednesday Night
Partly cloudy, with a low around 55.
Thursday
Mostly sunny, with a high near 76.
Thursday Night
Partly cloudy, with a low around 56.
Friday
Partly sunny, with a high near 77.
Friday Night
Partly cloudy, with a low around 55.
Saturday
Partly sunny, with a high near 80.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Belleville IL
 38.52°N 90.01°W (Elev. 535 ft)
Last Update:
1:26 am CDT Sep 20, 2026
Forecast Valid:
5am CDT Sep 20, 2026-6pm CDT Sep 26, 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

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation