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Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Mostly Cloudy

70°F

21°C

Humidity 71%
Wind Speed SE 5 mph
Barometer 29.92 in (1012.7 mb)
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Last update 21 Jun 12:53 am CDT
Extended Forecast for

Swansea IL

Flood Watch June 21, 07:00am until June 22, 07:00am
Click here for hazard details and duration
Flood Watch

  • Overnight

    Overnight: Mostly cloudy, with a low around 69. East wind around 6 mph.

    Low: 69 °F

    Mostly Cloudy

  • Sunday

    Sunday: Showers and thunderstorms likely, mainly after 1pm. Mostly cloudy, with a high near 86. Southeast wind 8 to 15 mph becoming southwest in the afternoon. Winds could gust as high as 28 mph. Chance of precipitation is 70%.

    High: 86 °F

    Chance
    T-storms then
    T-storms
    Likely

  • Sunday Night

    Sunday Night: Showers and thunderstorms, mainly before 11pm. Low around 66. South wind 7 to 11 mph becoming northwest after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 90%.

    Low: 66 °F

    T-storms then
    Chance
    T-storms

  • Monday

    Monday: Cloudy, then gradually becoming mostly sunny, with a high near 78. Northwest wind around 10 mph.

    High: 78 °F

    Decreasing
    Clouds

  • Monday Night

    Monday Night: Partly cloudy, with a low around 62. North wind 5 to 8 mph becoming calm in the evening.

    Low: 62 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 81.

    High: 81 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 64.

    Low: 64 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 84.

    High: 84 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 64.

    Low: 64 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly cloudy, with a low around 69. East wind around 6 mph.
Sunday
Showers and thunderstorms likely, mainly after 1pm. Mostly cloudy, with a high near 86. Southeast wind 8 to 15 mph becoming southwest in the afternoon. Winds could gust as high as 28 mph. Chance of precipitation is 70%.
Sunday Night
Showers and thunderstorms, mainly before 11pm. Low around 66. South wind 7 to 11 mph becoming northwest after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 90%.
Monday
Cloudy, then gradually becoming mostly sunny, with a high near 78. Northwest wind around 10 mph.
Monday Night
Partly cloudy, with a low around 62. North wind 5 to 8 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 81.
Tuesday Night
Mostly clear, with a low around 64.
Wednesday
Mostly sunny, with a high near 84.
Wednesday Night
Partly cloudy, with a low around 64.
Thursday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 83.
Thursday Night
A 20 percent chance of showers. Partly cloudy, with a low around 64.
Friday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 84.
Friday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 67.
Saturday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 86.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Swansea IL
 38.55°N 90.01°W (Elev. 548 ft)
Last Update:
11:51 pm CDT Jun 20, 2026
Forecast Valid:
1am CDT Jun 21, 2026-6pm CDT Jun 27, 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