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 >

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

87°F

31°C

Humidity 65%
Wind Speed Vrbl 3 mph
Barometer 30.25 in (1023.9 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index95°F (35°C)
Last update 16 Sep 10:53 am CDT
Extended Forecast for

2 Miles WSW Arnold MO

Heat Advisory September 16, 11:34am until September 19, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory September 16, 11:34am until September 19, 08:00pm

    NOW until 8:00pm Sat

    Heat Advisory

  • Today

    High: 95 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 7pm.  Partly cloudy, with a low around 76. Light south wind.

    Low: 76 °F

    Chance
    T-storms then
    Mostly Clear

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 4pm.  Sunny and hot, with a high near 99. Heat index values as high as 110. West wind around 5 mph becoming calm  in the afternoon.

    High: 99 °F

    Sunny then
    Slight Chance
    T-storms

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 73. Calm wind.

    Low: 73 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 96. Light and variable wind.

    High: 96 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 73.

    Low: 73 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny and hot, with a high near 98.

    High: 98 °F

    Hot

  • Saturday Night

    Saturday Night: A 20 percent chance of showers and thunderstorms after 1am.  Partly cloudy, with a low around 72.

    Low: 72 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

Detailed Forecast

Today
A 50 percent chance of showers and thunderstorms, mainly after 3pm. Partly sunny, with a high near 95. Heat index values as high as 107. South wind 3 to 5 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Partly cloudy, with a low around 76. Light south wind.
Thursday
A 20 percent chance of showers and thunderstorms after 4pm. Sunny and hot, with a high near 99. Heat index values as high as 110. West wind around 5 mph becoming calm in the afternoon.
Thursday Night
Partly cloudy, with a low around 73. Calm wind.
Friday
Mostly sunny, with a high near 96. Light and variable wind.
Friday Night
Partly cloudy, with a low around 73.
Saturday
Mostly sunny and hot, with a high near 98.
Saturday Night
A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 72.
Sunday
A 20 percent chance of showers. Mostly sunny, with a high near 94.
Sunday Night
A 30 percent chance of showers after 1am. Partly cloudy, with a low around 68.
Monday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 87.
Monday Night
A 30 percent chance of showers. Partly cloudy, with a low around 63.
Tuesday
A 20 percent chance of showers. Mostly sunny, with a high near 83.
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ABOUT THIS FORECAST

 
Point Forecast:
2 Miles WSW Arnold MO
 38.42°N 90.38°W (Elev. 495 ft)
11:31 am CDT Sep 16, 2026
11am 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