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 Lambert International Airport (KSTL)

Lat: 38.75°NLon: 90.37°WElev: 604ft.

Partly Cloudy

89°F

32°C

Humidity 57%
Wind Speed W 16 G 25 mph
Barometer 29.98 in (1013.8 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index96°F (36°C)
Last update 11 Aug 10:51 am CDT
Extended Forecast for

Florissant MO

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

    NOW until 8:00pm Wed

    Extreme Heat Warning

  • Today

    High: 98 °F

    Hot

  • Tonight

    Tonight: Partly cloudy, with a low around 80. South wind around 7 mph.

    Low: 80 °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 8 mph.  Chance of precipitation is 30%.

    High: 98 °F

    Scattered
    T-storms

  • Wednesday Night

    Wednesday Night: Scattered showers and thunderstorms, mainly after 5am.  Partly cloudy, with a low around 78. South wind around 6 mph.  Chance of precipitation is 30%.

    Low: 78 °F

    Scattered
    T-storms

  • Thursday

    Thursday: Scattered showers and thunderstorms, mainly before 7am.  Partly sunny, with a high near 95. Southeast wind 5 to 7 mph becoming east in the morning.  Chance of precipitation is 30%.

    High: 95 °F

    Scattered
    T-storms

  • Thursday Night

    Thursday Night: A 40 percent chance of showers and thunderstorms, mainly after 1am.  Mostly cloudy, with a low around 75.

    Low: 75 °F

    Chance
    T-storms

  • Friday

    Friday: Partly sunny, with a high near 93.

    High: 93 °F

    Partly Sunny

  • Friday Night

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

    Low: 76 °F

    Partly Cloudy

Detailed Forecast

Today
Sunny early, then becoming partly sunny and hot, with a high near 98. Heat index values as high as 110. Southwest wind 9 to 13 mph.
Tonight
Partly cloudy, with a low around 80. South wind around 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 8 mph. Chance of precipitation is 30%.
Wednesday Night
Scattered showers and thunderstorms, mainly after 5am. Partly cloudy, with a low around 78. South wind around 6 mph. Chance of precipitation is 30%.
Thursday
Scattered showers and thunderstorms, mainly before 7am. Partly sunny, with a high near 95. Southeast wind 5 to 7 mph becoming east in the morning. Chance of precipitation is 30%.
Thursday Night
A 40 percent chance of showers and thunderstorms, mainly after 1am. Mostly cloudy, with a low around 75.
Friday
Partly sunny, with a high near 93.
Friday Night
Partly cloudy, with a low around 76.
Saturday
Mostly sunny and hot, with a high near 98.
Saturday Night
Mostly clear, with a low around 79.
Sunday
Sunny and hot, with a high near 97.
Sunday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88.
Basemap Options
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ABOUT THIS FORECAST

 
Point Forecast:
Florissant MO
 38.8°N 90.34°W (Elev. 499 ft)
10:46 am CDT Aug 11, 2026
11am CDT Aug 11, 2026-6pm CDT Aug 17, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

National Digital Forecast Database