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

Strong Storms and Heavy Rainfall Threats; Dangerous Heat for Southern Plains into the Southwest

Thunderstorms, some severe, will impact areas of the Plains into the Midwest today. Rainfall can be locally heavy as well from these storms with isolated instances of flash flooding. Monsoonal flow will enhance rainfall across the Four Corners into the central Rockies today. Meanwhile, summer heat continues for the southern Plains, Southwest into southern California. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

86°F

30°C

Humidity 49%
Wind Speed SE 6 mph
Barometer 30.02 in
Dewpoint 64°F (18°C)
Visibility 10.00 mi
Heat Index88°F (31°C)
Last update 25 Aug 3:50 pm CDT
Extended Forecast for

Chesterfield IL

  • Tonight

    Tonight: Mostly cloudy, with a low around 66. Light southeast wind.

    Low: 66 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: A slight chance of showers, then a chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 88. Light and variable wind becoming west 5 to 8 mph in the morning. Chance of precipitation is 30%.

    High: 88 °F

    Mostly Sunny
    then Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 30 percent chance of showers and thunderstorms, mainly before 7pm. Partly cloudy, with a low around 63. Northeast wind around 6 mph becoming calm in the evening.

    Low: 63 °F

    Chance
    T-storms then
    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 85. Calm wind becoming north 5 to 7 mph in the morning.

    High: 85 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 61. North wind around 6 mph becoming calm in the evening.

    Low: 61 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 84.

    High: 84 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 60.

    Low: 60 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 86.

    High: 86 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 64.

    Low: 64 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 66. Light southeast wind.
Wednesday
A slight chance of showers, then a chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 88. Light and variable wind becoming west 5 to 8 mph in the morning. Chance of precipitation is 30%.
Wednesday Night
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Partly cloudy, with a low around 63. Northeast wind around 6 mph becoming calm in the evening.
Thursday
Sunny, with a high near 85. Calm wind becoming north 5 to 7 mph in the morning.
Thursday Night
Mostly clear, with a low around 61. North wind around 6 mph becoming calm in the evening.
Friday
Sunny, with a high near 84.
Friday Night
Mostly clear, with a low around 60.
Saturday
Sunny, with a high near 86.
Saturday Night
Partly cloudy, with a low around 64.
Sunday
Mostly sunny, with a high near 90.
Sunday Night
Partly cloudy, with a low around 70.
Monday
Mostly sunny, with a high near 92.
Monday Night
A 30 percent chance of showers. Partly cloudy, with a low around 71.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 90.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Chesterfield IL
 39.26°N 90.06°W (Elev. 600 ft)
Last Update:
1:26 pm CDT Aug 25, 2026
Forecast Valid:
4pm CDT Aug 25, 2026-6pm CDT Sep 1, 2026
 
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Additional Resources

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Chance of Precipitation