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

79°F

26°C

Humidity 47%
Wind Speed Vrbl 3 mph
Barometer 30.04 in (1016.9 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 10 Oct 1:53 pm CDT
Extended Forecast for

Herculaneum MO

  • This Afternoon

    This Afternoon: Partly sunny, with a high near 79. East wind around 6 mph.

    High: 79 °F

    Partly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 51. East wind around 5 mph becoming calm in the evening.

    Low: 51 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 89. Calm wind.

    High: 89 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 61. Light and variable wind.

    Low: 61 °F

    Partly Cloudy

  • Columbus Day

    Columbus Day: Sunny, with a high near 95. Southwest wind 5 to 9 mph.

    High: 95 °F

    Sunny

  • Monday Night

    Monday Night: Clear, with a low around 67.

    Low: 67 °F

    Clear

  • Tuesday

    Tuesday: Sunny, with a high near 93.

    High: 93 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 68.

    Low: 68 °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

Detailed Forecast

This Afternoon
Partly sunny, with a high near 79. East wind around 6 mph.
Tonight
Partly cloudy, with a low around 51. East wind around 5 mph becoming calm in the evening.
Sunday
Sunny, with a high near 89. Calm wind.
Sunday Night
Partly cloudy, with a low around 61. Light and variable wind.
Columbus Day
Sunny, with a high near 95. Southwest wind 5 to 9 mph.
Monday Night
Clear, with a low around 67.
Tuesday
Sunny, with a high near 93.
Tuesday Night
A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 68.
Wednesday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 85. Chance of precipitation is 70%.
Wednesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 63. Chance of precipitation is 60%.
Thursday
Showers and thunderstorms likely. Mostly cloudy, with a high near 80. Chance of precipitation is 60%.
Thursday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 54.
Friday
A 20 percent chance of showers. Partly sunny, with a high near 72.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Herculaneum MO
 38.27°N 90.39°W (Elev. 456 ft)
Last Update:
1:26 pm CDT Oct 10, 2026
Forecast Valid:
2pm CDT Oct 10, 2026-6pm CDT Oct 16, 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