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Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

81°F

27°C

Humidity 85%
Wind Speed S 3 mph
Barometer 29.99 in (1015.2 mb)
Dewpoint 76°F (24°C)
Visibility 10.00 mi
Heat Index87°F (31°C)
Last update 26 Jul 12:53 am CDT
Extended Forecast for

Swansea IL

Extreme Heat Warning July 26, 01:09am until July 29, 07:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning July 26, 01:09am until July 29, 07:00pm

    NOW until 7:00pm Tue

    Extreme Heat Warning

  • Overnight

    Low: 75 °F

    Partly Cloudy

  • Saturday

    Saturday: A 20 percent chance of showers and thunderstorms after 3pm. Mostly sunny, with a high near 94. Heat index values as high as 107. South wind 5 to 10 mph.

    High: 94 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Saturday Night

    Saturday Night: A 20 percent chance of showers and thunderstorms before 10pm. Partly cloudy, with a low around 76. South wind 5 to 8 mph.

    Low: 76 °F

    Slight Chance
    T-storms then
    Partly Cloudy

  • Sunday

    Sunday: A 30 percent chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 94. Heat index values as high as 109. South wind 5 to 7 mph.

    High: 94 °F

    Chance
    T-storms

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 78. South wind around 5 mph becoming calm in the evening.

    Low: 78 °F

    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 99.

    High: 99 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 79.

    Low: 79 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms after 1pm. Sunny and hot, with a high near 99.

    High: 99 °F

    Sunny then
    Slight Chance
    T-storms

Detailed Forecast

Overnight
Partly cloudy, with a low around 75. South wind around 5 mph.
Saturday
A 20 percent chance of showers and thunderstorms after 3pm. Mostly sunny, with a high near 94. Heat index values as high as 107. South wind 5 to 10 mph.
Saturday Night
A 20 percent chance of showers and thunderstorms before 10pm. Partly cloudy, with a low around 76. South wind 5 to 8 mph.
Sunday
A 30 percent chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 94. Heat index values as high as 109. South wind 5 to 7 mph.
Sunday Night
Mostly clear, with a low around 78. South wind around 5 mph becoming calm in the evening.
Monday
Sunny and hot, with a high near 99.
Monday Night
Mostly clear, with a low around 79.
Tuesday
A 20 percent chance of showers and thunderstorms after 1pm. Sunny and hot, with a high near 99.
Tuesday Night
A 20 percent chance of showers and thunderstorms. Mostly clear, with a low around 77.
Wednesday
A 40 percent chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 92.
Wednesday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72.
Thursday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 85.
Thursday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 66.
Friday
Mostly sunny, with a high near 83.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Swansea IL
 38.52°N 89.98°W (Elev. 509 ft)
Last Update:
10:21 pm CDT Jul 25, 2025
Forecast Valid:
1am CDT Jul 26, 2025-6pm CDT Aug 1, 2025
 
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