Severe Thunderstorms and Heavy Rain Across the Ohio Valley;

Severe thunderstorms with damaging wind gusts will be possible from the mid-Mississippi Valley into parts of the Ohio Valley and central Appalachians. Heavy rain associated with these storms may lead to considerable flash and urban flooding impacts across portions of the Ohio Valley. Mid-summer heat persists from the Central Plains to the Southeast. Read More >

Current conditions at

St. Louis, Spirit Of St. Louis Airport (KSUS)

Lat: 38.66°NLon: 90.66°WElev: 463ft.

Fair

92°F

33°C

Humidity 60%
Wind Speed SW 9 mph
Barometer 29.87 in (1010.3 mb)
Dewpoint 76°F (24°C)
Visibility 10.00 mi
Heat Index105°F (41°C)
Last update 11 Aug 5:54 pm CDT
Extended Forecast for

Clarkson Valley MO

Extreme Heat Warning August 11, 06:45pm until August 12, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 11, 06:45pm until August 12, 08:00pm

    NOW until 8:00pm Wed

    Extreme Heat Warning

  • Tonight

    Low: 79 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Scattered showers and thunderstorms, mainly between 10am and 11am.  Mostly sunny and hot, with a high near 98. Heat index values as high as 110. Southwest wind around 7 mph.  Chance of precipitation is 30%.

    High: 98 °F

    Scattered
    T-storms

  • Wednesday Night

    Wednesday Night: Isolated showers and thunderstorms.  Partly cloudy, with a low around 77. South wind around 6 mph.  Chance of precipitation is 20%.

    Low: 77 °F

    Isolated
    T-storms

  • Thursday

    Thursday: Mostly sunny and hot, with a high near 97. Heat index values as high as 109. Southwest wind around 6 mph.

    High: 97 °F

    Hot

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 76. Light and variable wind becoming south around 5 mph in the evening.

    Low: 76 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 96.

    High: 96 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 76.

    Low: 76 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny and hot, with a high near 98.

    High: 98 °F

    Hot

Detailed Forecast

Tonight
Partly cloudy, with a low around 79. South wind 5 to 7 mph.
Wednesday
Scattered showers and thunderstorms, mainly between 10am and 11am. Mostly sunny and hot, with a high near 98. Heat index values as high as 110. Southwest wind around 7 mph. Chance of precipitation is 30%.
Wednesday Night
Isolated showers and thunderstorms. Partly cloudy, with a low around 77. South wind around 6 mph. Chance of precipitation is 20%.
Thursday
Mostly sunny and hot, with a high near 97. Heat index values as high as 109. Southwest wind around 6 mph.
Thursday Night
Partly cloudy, with a low around 76. Light and variable wind becoming south around 5 mph in the evening.
Friday
Mostly sunny, with a high near 96.
Friday Night
Partly cloudy, with a low around 76.
Saturday
Sunny and hot, with a high near 98.
Saturday Night
Mostly clear, with a low around 77.
Sunday
Sunny and hot, with a high near 97.
Sunday Night
Partly cloudy, with a low around 75.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 89.
Monday Night
Partly cloudy, with a low around 71.
Tuesday
Mostly sunny, with a high near 90.
Basemap Options
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ABOUT THIS FORECAST

 
Point Forecast:
Clarkson Valley MO
 38.63°N 90.6°W (Elev. 597 ft)
5:06 pm CDT Aug 11, 2026
6pm CDT Aug 11, 2026-6pm CDT Aug 18, 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