Dangerous Heat in the Southwest; Severe Thunderstorms and Heavy Rain in the Northeast and Mid-Atlantic

Dangerous heat will persist across the Southwest U.S. through Friday with daytime highs of 110-115°F. Heat across the southern Plains will briefly ease to near-normal by late week. Strong to severe thunderstorms may produce damaging wind, hail, a tornado or two, heavy rain and flash flooding across parts of the Mid-Atlantic and Northeast. Heavy rainfall threat continues across the Gulf Coast. Read More >

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

A Few Clouds

85°F

29°C

Humidity 45%
Wind Speed N 12 mph
Barometer 30.03 in (1016.5 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 27 Aug 2:53 pm CDT
Extended Forecast for

Herculaneum MO

  • Tonight

    Tonight: Mostly clear, with a low around 63. North wind around 5 mph becoming calm  in the evening.

    Low: 63 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 87. Light and variable wind.

    High: 87 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 61. Calm wind.

    Low: 61 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 89. Calm wind becoming south around 5 mph in the afternoon.

    High: 89 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 66. Light south wind.

    Low: 66 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 95.

    High: 95 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 71.

    Low: 71 °F

    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 97.

    High: 97 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 74.

    Low: 74 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly clear, with a low around 63. North wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 87. Light and variable wind.
Friday Night
Mostly clear, with a low around 61. Calm wind.
Saturday
Sunny, with a high near 89. Calm wind becoming south around 5 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 66. Light south wind.
Sunday
Sunny, with a high near 95.
Sunday Night
Mostly clear, with a low around 71.
Monday
Sunny and hot, with a high near 97.
Monday Night
Mostly clear, with a low around 74.
Tuesday
Sunny and hot, with a high near 97.
Tuesday Night
Mostly clear, with a low around 75.
Wednesday
Sunny and hot, with a high near 97.
Wednesday Night
Mostly clear, with a low around 76.
Thursday
Sunny and hot, with a high near 97.
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ABOUT THIS FORECAST

 
Point Forecast:
Herculaneum MO
 38.27°N 90.39°W (Elev. 456 ft)
1:26 pm CDT Aug 27, 2026
3pm CDT Aug 27, 2026-6pm CDT Sep 3, 2026
 
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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