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

91°F

33°C

Humidity 54%
Wind Speed Calm
Barometer 30.14 in (1020.1 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index99°F (37°C)
Last update 18 Sep 11:53 am CDT
Extended Forecast for

Millstadt ILSimilar City Names

Heat Advisory September 18, 01:06pm until September 19, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory September 18, 01:06pm until September 19, 08:00pm

    NOW until 8:00pm Sat

    Heat Advisory

  • This Afternoon

    High: 95 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 20 percent chance of showers and thunderstorms before 10pm.  Mostly clear, with a low around 73. Calm wind becoming south around 5 mph after midnight.

    Low: 73 °F

    Slight Chance
    T-storms then
    Mostly Clear

  • Saturday

    Saturday: Increasing clouds and hot, with a high near 97. Heat index values as high as 100. Southwest wind 5 to 7 mph.

    High: 97 °F

    Hot

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 73. Southwest wind 3 to 6 mph.

    Low: 73 °F

    Partly Cloudy

  • Sunday

    Sunday: A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm.  Mostly sunny, with a high near 93. Northwest wind around 6 mph.  Chance of precipitation is 20%.

    High: 93 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Sunday Night

    Sunday Night: A 50 percent chance of showers and thunderstorms, mainly after 1am.  Mostly cloudy, with a low around 68.

    Low: 68 °F

    Slight Chance
    T-storms then
    Chance
    T-storms

  • Monday

    Monday: Showers likely, with thunderstorms also possible after 1pm.  Mostly cloudy, with a high near 82. Chance of precipitation is 60%.

    High: 82 °F

    Showers
    Likely

  • Monday Night

    Monday Night: A 30 percent chance of showers and thunderstorms.  Mostly cloudy, with a low around 60.

    Low: 60 °F

    Chance
    Showers

Detailed Forecast

This Afternoon
A 30 percent chance of showers and thunderstorms, mainly after 5pm. Sunny, with a high near 95. Heat index values as high as 106. Calm wind.
Tonight
A 20 percent chance of showers and thunderstorms before 10pm. Mostly clear, with a low around 73. Calm wind becoming south around 5 mph after midnight.
Saturday
Increasing clouds and hot, with a high near 97. Heat index values as high as 100. Southwest wind 5 to 7 mph.
Saturday Night
Partly cloudy, with a low around 73. Southwest wind 3 to 6 mph.
Sunday
A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Mostly sunny, with a high near 93. Northwest wind around 6 mph. Chance of precipitation is 20%.
Sunday Night
A 50 percent chance of showers and thunderstorms, mainly after 1am. Mostly cloudy, with a low around 68.
Monday
Showers likely, with thunderstorms also possible after 1pm. Mostly cloudy, with a high near 82. Chance of precipitation is 60%.
Monday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 60.
Tuesday
Partly sunny, with a high near 72.
Tuesday Night
Mostly cloudy, with a low around 55.
Wednesday
Mostly sunny, with a high near 74.
Wednesday Night
Partly cloudy, with a low around 54.
Thursday
Mostly sunny, with a high near 76.
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ABOUT THIS FORECAST

 
Point Forecast:
Millstadt ILSimilar City Names
 38.46°N 90.1°W (Elev. 604 ft)
10:41 am CDT Sep 18, 2026
1pm CDT Sep 18, 2026-6pm CDT Sep 24, 2026
 
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Additional Resources

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