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.

A Few Clouds

70°F

21°C

Humidity 84%
Wind Speed S 8 G 18 mph
Barometer 29.98 in (1014.9 mb)
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Last update 20 Sep 8:53 pm CDT
Extended Forecast for

Swansea IL

  • Tonight

    Tonight: Isolated showers and thunderstorms. Mostly cloudy, with a low around 66. South wind 3 to 5 mph. Chance of precipitation is 20%.

    Low: 66 °F

    Isolated
    T-storms

  • Sunday

    Sunday: A 50 percent chance of showers and thunderstorms, mainly after 10am. Partly sunny, with a high near 85. Southwest wind 3 to 8 mph.

    High: 85 °F

    Chance
    T-storms

  • Sunday Night

    Sunday Night: Showers and thunderstorms. Low around 67. Southwest wind 3 to 6 mph. Chance of precipitation is 80%.

    Low: 67 °F

    T-storms

  • Monday

    Monday: Showers and thunderstorms before 8am, then showers and possibly a thunderstorm, mainly after 8am. High near 82. South wind 6 to 9 mph. Chance of precipitation is 80%.

    High: 82 °F

    T-storms then
    Showers

  • Monday Night

    Monday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 66. South wind 3 to 6 mph. Chance of precipitation is 60%.

    Low: 66 °F

    Chance
    T-storms then
    Showers
    Likely

  • Tuesday

    Tuesday: A chance of showers, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Chance of precipitation is 60%.

    High: 78 °F

    Showers
    Likely

  • Tuesday Night

    Tuesday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 66. Chance of precipitation is 60%.

    Low: 66 °F

    Showers
    Likely

  • Wednesday

    Wednesday: Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 77. Chance of precipitation is 60%.

    High: 77 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63.

    Low: 63 °F

    Chance
    T-storms

Detailed Forecast

Tonight
Isolated showers and thunderstorms. Mostly cloudy, with a low around 66. South wind 3 to 5 mph. Chance of precipitation is 20%.
Sunday
A 50 percent chance of showers and thunderstorms, mainly after 10am. Partly sunny, with a high near 85. Southwest wind 3 to 8 mph.
Sunday Night
Showers and thunderstorms. Low around 67. Southwest wind 3 to 6 mph. Chance of precipitation is 80%.
Monday
Showers and thunderstorms before 8am, then showers and possibly a thunderstorm, mainly after 8am. High near 82. South wind 6 to 9 mph. Chance of precipitation is 80%.
Monday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 66. South wind 3 to 6 mph. Chance of precipitation is 60%.
Tuesday
A chance of showers, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Chance of precipitation is 60%.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 66. Chance of precipitation is 60%.
Wednesday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 77. Chance of precipitation is 60%.
Wednesday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63.
Thursday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 75. Chance of precipitation is 50%.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 59.
Friday
A 20 percent chance of showers. Mostly sunny, with a high near 77.
Friday Night
Partly cloudy, with a low around 59.
Saturday
Mostly sunny, with a high near 78.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Swansea IL
 38.55°N 89.98°W (Elev. 551 ft)
Last Update:
6:16 pm CDT Sep 20, 2025
Forecast Valid:
10pm CDT Sep 20, 2025-6pm CDT Sep 27, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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