Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56° N Lon: 90.15° W Elev: 410 ft.

Fair

66°F

19°C

Humidity 40%
Wind Speed SE 8 mph
Barometer 30.19 in (1022.3 mb)
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Last update 20 Apr 5:53 pm CDT
Detailed forecast for

St. Clair County

Tonight
Mostly clear. Lows around 50. Southeast winds 5 to 10 mph, becoming south after midnight.
Tuesday
Sunny. Not as cool with highs in the upper 70s. Southwest winds 10 to 15 mph with gusts up to 25 mph.
Tuesday Night
Mostly clear. Lows in the mid 50s. Southwest winds 10 to 15 mph.
Wednesday
Sunny. Highs in the upper 70s. Southwest winds 5 to 10 mph.
Wednesday Night
Mostly clear. Lows in the upper 50s. South winds 5 to 10 mph.
Thursday
Mostly sunny. Highs in the lower 80s.
Thursday Night
Partly cloudy with a slight chance of showers and thunderstorms in the evening, then mostly cloudy with showers likely with a chance of thunderstorms after midnight. Lows in the lower 60s. Chance of rain 70 percent.
Friday
A chance of thunderstorms. Showers. Highs in the mid 70s. Chance of rain 90 percent.
Friday Night
Mostly cloudy in the evening, then becoming partly cloudy. A chance of showers. A chance of thunderstorms, mainly in the evening. Cooler with lows in the lower 50s. Chance of rain 50 percent.
Saturday
Mostly sunny with a slight chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the lower 70s. Chance of rain 20 percent.
Saturday Night And Sunday
Mostly cloudy. A chance of showers with a slight chance of thunderstorms. Lows in the lower 50s. Highs in the lower 70s. Chance of rain 30 percent.
Sunday Night
Mostly cloudy with a 50 percent chance of showers. Lows in the mid 50s.
Monday
Mostly cloudy in the morning, then becoming partly sunny. A chance of showers. A slight chance of thunderstorms in the afternoon. Highs in the lower 70s. Chance of rain 50 percent.



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553 PM CDT Mon Apr 20 2026
 
 

Additional Resources

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