Thunderstorms and Heavy Rain in the Mid-South; Heat Continues in the Southeast and Southwest

Severe thunderstorms and heavy rain are expected across portions of the mid-Mississippi Valley into the Ohio Valley and portions of Arizona. Dangerous heat persists in the South and Southeast while building into the Southwest. Overnight lows will be so warm that, when combined with oppressive dew points, little-to-no relief from the scorching daytime highs will be available. Read More >

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

73°F

23°C

Humidity 94%
Wind Speed Calm
Barometer 29.94 in (1013.6 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 18 Aug 10:53 pm CDT
Extended Forecast for

Festus MO

  • Tonight

    Tonight: Showers and thunderstorms likely, mainly after 4am.  Mostly clear early, then becoming mostly cloudy, with a low around 69. Calm wind.  Chance of precipitation is 60%.

    Low: 69 °F

    T-storms
    Likely

  • Wednesday

    Wednesday: Showers and thunderstorms, mainly before 10am. Some of the storms could produce heavy rainfall.  High near 83. Light and variable wind.  Chance of precipitation is 90%.

    High: 83 °F

    Heavy Rain
    then Slight
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 50 percent chance of showers and thunderstorms, mainly before midnight.  Mostly cloudy, with a low around 66. Calm wind.

    Low: 66 °F

    Chance
    T-storms then
    Slight Chance
    T-storms

  • Thursday

    Thursday: Mostly cloudy, then gradually becoming sunny, with a high near 84. Light north wind.

    High: 84 °F

    Decreasing
    Clouds

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 63. Calm wind.

    Low: 63 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 87.

    High: 87 °F

    Sunny

  • Friday Night

    Friday Night: A 20 percent chance of showers before 1am.  Mostly clear, with a low around 65.

    Low: 65 °F

    Slight Chance
    Showers

  • Saturday

    Saturday: A slight chance of showers, with thunderstorms also possible after 1pm.  Sunny, with a high near 88. Chance of precipitation is 20%.

    High: 88 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 64.

    Low: 64 °F

    Mostly Clear

Detailed Forecast

Tonight
Showers and thunderstorms likely, mainly after 4am. Mostly clear early, then becoming mostly cloudy, with a low around 69. Calm wind. Chance of precipitation is 60%.
Wednesday
Showers and thunderstorms, mainly before 10am. Some of the storms could produce heavy rainfall. High near 83. Light and variable wind. Chance of precipitation is 90%.
Wednesday Night
A 50 percent chance of showers and thunderstorms, mainly before midnight. Mostly cloudy, with a low around 66. Calm wind.
Thursday
Mostly cloudy, then gradually becoming sunny, with a high near 84. Light north wind.
Thursday Night
Mostly clear, with a low around 63. Calm wind.
Friday
Sunny, with a high near 87.
Friday Night
A 20 percent chance of showers before 1am. Mostly clear, with a low around 65.
Saturday
A slight chance of showers, with thunderstorms also possible after 1pm. Sunny, with a high near 88. Chance of precipitation is 20%.
Saturday Night
Mostly clear, with a low around 64.
Sunday
Mostly sunny, with a high near 84.
Sunday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 87.
Monday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 67.
Tuesday
A 20 percent chance of showers. Mostly sunny, with a high near 89.
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ABOUT THIS FORECAST

 
Point Forecast:
Festus MO
 38.22°N 90.42°W (Elev. 499 ft)
10:26 pm CDT Aug 18, 2026
11pm CDT Aug 18, 2026-6pm CDT Aug 25, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

National Digital Forecast Database