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

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

81°F

27°C

Humidity 37%
Wind Speed SE 9 mph
Barometer 29.99 in (1015.3 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 10 Oct 3:53 pm CDT
Extended Forecast for

Swansea IL

  • Tonight

    Tonight: Mostly cloudy, then gradually becoming mostly clear, with a low around 54. Southeast wind 5 to 7 mph becoming calm in the evening.

    Low: 54 °F

    Decreasing
    Clouds

  • Sunday

    Sunday: Sunny, with a high near 87. Calm wind.

    High: 87 °F

    Sunny

  • Sunday Night

    Sunday Night: Increasing clouds, with a low around 62. Calm wind becoming south around 5 mph after midnight.

    Low: 62 °F

    Increasing
    Clouds

  • Columbus Day

    Columbus Day: Partly sunny, then gradually becoming sunny, with a high near 95. Southwest wind 5 to 11 mph.

    High: 95 °F

    Becoming
    Sunny

  • Monday Night

    Monday Night: Clear, with a low around 69. Southwest wind 7 to 10 mph.

    Low: 69 °F

    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 92.

    High: 92 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 69.

    Low: 69 °F

    Mostly Clear
    then Chance
    Showers

  • Wednesday

    Wednesday: Showers likely and possibly a thunderstorm. Partly sunny, with a high near 85. Chance of precipitation is 70%.

    High: 85 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: Showers likely, with thunderstorms also possible after 1am. Mostly cloudy, with a low around 65. Chance of precipitation is 60%.

    Low: 65 °F

    Showers
    Likely

Detailed Forecast

Tonight
Mostly cloudy, then gradually becoming mostly clear, with a low around 54. Southeast wind 5 to 7 mph becoming calm in the evening.
Sunday
Sunny, with a high near 87. Calm wind.
Sunday Night
Increasing clouds, with a low around 62. Calm wind becoming south around 5 mph after midnight.
Columbus Day
Partly sunny, then gradually becoming sunny, with a high near 95. Southwest wind 5 to 11 mph.
Monday Night
Clear, with a low around 69. Southwest wind 7 to 10 mph.
Tuesday
Sunny, with a high near 92.
Tuesday Night
A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 69.
Wednesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 85. Chance of precipitation is 70%.
Wednesday Night
Showers likely, with thunderstorms also possible after 1am. Mostly cloudy, with a low around 65. Chance of precipitation is 60%.
Thursday
Showers likely, with thunderstorms also possible after 1pm. Mostly cloudy, with a high near 79. Chance of precipitation is 60%.
Thursday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 57.
Friday
A 20 percent chance of showers. Partly sunny, with a high near 72.
Friday Night
Partly cloudy, with a low around 47.
Saturday
Mostly sunny, with a high near 65.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Swansea IL
 38.52°N 89.98°W (Elev. 509 ft)
Last Update:
2:51 pm CDT Oct 10, 2026
Forecast Valid:
4pm CDT Oct 10, 2026-6pm CDT Oct 17, 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