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.

Fair

43°F

6°C

Humidity 47%
Wind Speed NE 14 mph
Barometer 30.09 in (1019.0 mb)
Dewpoint 24°F (-4°C)
Visibility 10.00 mi
Wind Chill36°F (2°C)
Last update 14 Mar 1:54 am CDT
Extended Forecast for

4 Miles E Portage Des Sioux MO

  • Overnight

    Overnight: Partly cloudy, with a low around 36. Northeast wind 3 to 5 mph.

    Low: 36 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 63. Southeast wind 6 to 15 mph, with gusts as high as 23 mph.

    High: 63 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 53. South wind 11 to 14 mph, with gusts as high as 24 mph.

    Low: 53 °F

    Partly Cloudy

  • Sunday

    Sunday: Rain, mainly after 1pm. High near 68. Breezy, with a south wind 18 to 23 mph, with gusts as high as 38 mph. Chance of precipitation is 90%.

    High: 68 °F

    Breezy.
    Chance Rain
    then Rain

  • Sunday Night

    Sunday Night: Rain before 10pm, then snow, possibly mixed with rain between 10pm and 1am, then a chance of snow after 1am. Low around 20. Blustery, with a northwest wind 22 to 26 mph, with gusts as high as 43 mph. Chance of precipitation is 90%. New snow accumulation of less than one inch possible.

    Low: 20 °F

    Rain/Snow and
    Blustery

  • Monday

    Monday: A 30 percent chance of snow before 1pm. Mostly cloudy, with a high near 28. Blustery.

    High: 28 °F

    Chance Snow
    and Blustery

  • Monday Night

    Monday Night: Partly cloudy, with a low around 12.

    Low: 12 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 37.

    High: 37 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: A chance of snow before 1am, then a chance of rain and snow. Mostly cloudy, with a low around 30. Chance of precipitation is 30%.

    Low: 30 °F

    Chance Snow
    then Chance
    Rain/Snow

Detailed Forecast

Overnight
Partly cloudy, with a low around 36. Northeast wind 3 to 5 mph.
Saturday
Mostly sunny, with a high near 63. Southeast wind 6 to 15 mph, with gusts as high as 23 mph.
Saturday Night
Partly cloudy, with a low around 53. South wind 11 to 14 mph, with gusts as high as 24 mph.
Sunday
Rain, mainly after 1pm. High near 68. Breezy, with a south wind 18 to 23 mph, with gusts as high as 38 mph. Chance of precipitation is 90%.
Sunday Night
Rain before 10pm, then snow, possibly mixed with rain between 10pm and 1am, then a chance of snow after 1am. Low around 20. Blustery, with a northwest wind 22 to 26 mph, with gusts as high as 43 mph. Chance of precipitation is 90%. New snow accumulation of less than one inch possible.
Monday
A 30 percent chance of snow before 1pm. Mostly cloudy, with a high near 28. Blustery.
Monday Night
Partly cloudy, with a low around 12.
Tuesday
Mostly sunny, with a high near 37.
Tuesday Night
A chance of snow before 1am, then a chance of rain and snow. Mostly cloudy, with a low around 30. Chance of precipitation is 30%.
Wednesday
Partly sunny, with a high near 65.
Wednesday Night
Mostly clear, with a low around 39.
Thursday
Sunny, with a high near 71.
Thursday Night
Partly cloudy, with a low around 46.
Friday
Sunny, with a high near 71.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles E Portage Des Sioux MO
 38.93°N 90.27°W (Elev. 407 ft)
Last Update:
1:26 am CDT Mar 14, 2026
Forecast Valid:
2am CDT Mar 14, 2026-6pm CDT Mar 20, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation