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

Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

93°F

34°C

Humidity 68%
Wind Speed Calm
Barometer 29.93 in (1013.1 mb)
Dewpoint 81°F (27°C)
Visibility 10.00 mi
Heat Index114°F (46°C)
Last update 26 Jul 11:53 am CDT
Extended Forecast for

4 Miles SE Swansea IL

Extreme Heat Warning until July 27, 09:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning until July 27, 09:00pm

    NOW until 9:00pm Mon

    Extreme Heat Warning

  • This Afternoon

    High: 96 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 7pm. Partly cloudy, with a low around 77. Calm wind.

    Low: 77 °F

    Chance
    T-storms then
    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 96. Heat index values as high as 115. South wind 3 to 8 mph.

    High: 96 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 78. South wind around 6 mph becoming west after midnight.

    Low: 78 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 93. Northwest wind 6 to 9 mph.

    High: 93 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 71.

    Low: 71 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Sunny, with a high near 88.

    High: 88 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 66.

    Low: 66 °F

    Mostly Clear

Detailed Forecast

This Afternoon
A 30 percent chance of showers and thunderstorms, mainly after 4pm. Mostly sunny, with a high near 96. Heat index values as high as 116. West wind 3 to 5 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Partly cloudy, with a low around 77. Calm wind.
Monday
Sunny, with a high near 96. Heat index values as high as 115. South wind 3 to 8 mph.
Monday Night
Mostly clear, with a low around 78. South wind around 6 mph becoming west after midnight.
Tuesday
Mostly sunny, with a high near 93. Northwest wind 6 to 9 mph.
Tuesday Night
Partly cloudy, with a low around 71.
Wednesday
Sunny, with a high near 88.
Wednesday Night
Mostly clear, with a low around 66.
Thursday
Sunny, with a high near 88.
Thursday Night
Partly cloudy, with a low around 69.
Friday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 86.
Friday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 68.
Saturday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 85.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SE Swansea IL
 38.5°N 89.95°W (Elev. 499 ft)
Last Update:
11:21 am CDT Jul 26, 2026
Forecast Valid:
12pm CDT Jul 26, 2026-6pm CDT Aug 1, 2026
 
Forecast Discussion
 
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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