National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

St. Charles, St. Charles County Smartt Airport (KSET)

Lat: 38.93°NLon: 90.43°WElev: 436ft.

Mostly Cloudy

71°F

22°C

Humidity 87%
Wind Speed Calm
Barometer 30.04 in (1017.0 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 14 Oct 10:54 pm CDT
Extended Forecast for

Portage Des Sioux MO

  • Tonight

    Tonight: Scattered showers, mainly after 4am. Mostly cloudy, with a low around 66. Light and variable wind. Chance of precipitation is 30%.

    Low: 66 °F

    Scattered
    Showers

  • Thursday

    Thursday: Showers and thunderstorms before 10am, then showers likely and possibly a thunderstorm between 10am and noon, then a chance of showers and thunderstorms after noon. High near 80. East wind 5 to 11 mph becoming southwest in the afternoon. Chance of precipitation is 80%.

    High: 80 °F

    Showers then
    Chance
    T-storms

  • Thursday Night

    Thursday Night: Showers and thunderstorms likely before 1am, then a slight chance of showers between 1am and 2am. Increasing clouds, with a low around 46. Northwest wind 13 to 17 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.

    Low: 46 °F

    Showers
    Likely

  • Friday

    Friday: Partly sunny, with a high near 58. Breezy, with a northwest wind 18 to 22 mph, with gusts as high as 31 mph.

    High: 58 °F

    Partly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 39. North wind 8 to 17 mph, with gusts as high as 25 mph.

    Low: 39 °F

    Mostly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 63.

    High: 63 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 38.

    Low: 38 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 68.

    High: 68 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 42.

    Low: 42 °F

    Mostly Clear

Detailed Forecast

Tonight
Scattered showers, mainly after 4am. Mostly cloudy, with a low around 66. Light and variable wind. Chance of precipitation is 30%.
Thursday
Showers and thunderstorms before 10am, then showers likely and possibly a thunderstorm between 10am and noon, then a chance of showers and thunderstorms after noon. High near 80. East wind 5 to 11 mph becoming southwest in the afternoon. Chance of precipitation is 80%.
Thursday Night
Showers and thunderstorms likely before 1am, then a slight chance of showers between 1am and 2am. Increasing clouds, with a low around 46. Northwest wind 13 to 17 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.
Friday
Partly sunny, with a high near 58. Breezy, with a northwest wind 18 to 22 mph, with gusts as high as 31 mph.
Friday Night
Mostly cloudy, with a low around 39. North wind 8 to 17 mph, with gusts as high as 25 mph.
Saturday
Sunny, with a high near 63.
Saturday Night
Clear, with a low around 38.
Sunday
Sunny, with a high near 68.
Sunday Night
Mostly clear, with a low around 42.
Monday
Mostly sunny, with a high near 74.
Monday Night
Partly cloudy, with a low around 45.
Tuesday
Mostly sunny, with a high near 77.
Tuesday Night
Mostly clear, with a low around 51.
Wednesday
Sunny, with a high near 81.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Portage Des Sioux MO
 38.93°N 90.33°W (Elev. 407 ft)
Last Update:
10:21 pm CDT Oct 14, 2026
Forecast Valid:
11pm CDT Oct 14, 2026-6pm CDT Oct 21, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation