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.

Rain Fog/Mist

68°F

20°C

Humidity 93%
Wind Speed NE 3 mph
Barometer 30.01 in (1016.0 mb)
Dewpoint 66°F (19°C)
Visibility 1.75 mi
Last update 15 Oct 7:54 am CDT
Extended Forecast for

Dow IL

  • Today

    Today: Showers and possibly a thunderstorm, mainly before 1pm, then a chance of showers and thunderstorms after 1pm. Patchy fog before 11am. High near 79. Southeast wind 6 to 13 mph becoming southwest in the afternoon. Chance of precipitation is 90%.

    High: 79 °F

    Showers and
    Patchy Fog
    then Showers
    Likely

  • Tonight

    Tonight: Showers and thunderstorms likely before 1am, then isolated showers between 1am and 2am. Mostly cloudy, with a low around 45. Southwest wind 14 to 18 mph becoming northwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 60%.

    Low: 45 °F

    Showers
    Likely

  • Friday

    Friday: Partly sunny, with a high near 57. Breezy, with a northwest wind 20 to 22 mph, with gusts as high as 31 mph.

    High: 57 °F

    Partly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 37. Breezy, with a north wind 10 to 20 mph, with gusts as high as 28 mph.

    Low: 37 °F

    Mostly Cloudy
    and Breezy
    then Partly
    Cloudy

  • Saturday

    Saturday: Sunny, with a high near 61. North wind 5 to 7 mph becoming calm in the afternoon.

    High: 61 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 37.

    Low: 37 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 67.

    High: 67 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 38.

    Low: 38 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 72.

    High: 72 °F

    Mostly Sunny

Detailed Forecast

Today
Showers and possibly a thunderstorm, mainly before 1pm, then a chance of showers and thunderstorms after 1pm. Patchy fog before 11am. High near 79. Southeast wind 6 to 13 mph becoming southwest in the afternoon. Chance of precipitation is 90%.
Tonight
Showers and thunderstorms likely before 1am, then isolated showers between 1am and 2am. Mostly cloudy, with a low around 45. Southwest wind 14 to 18 mph becoming northwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 60%.
Friday
Partly sunny, with a high near 57. Breezy, with a northwest wind 20 to 22 mph, with gusts as high as 31 mph.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 37. Breezy, with a north wind 10 to 20 mph, with gusts as high as 28 mph.
Saturday
Sunny, with a high near 61. North wind 5 to 7 mph becoming calm in the afternoon.
Saturday Night
Clear, with a low around 37.
Sunday
Sunny, with a high near 67.
Sunday Night
Mostly clear, with a low around 38.
Monday
Mostly sunny, with a high near 72.
Monday Night
Partly cloudy, with a low around 41.
Tuesday
Sunny, with a high near 74.
Tuesday Night
Mostly clear, with a low around 44.
Wednesday
Sunny, with a high near 77.
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ABOUT THIS FORECAST

 
Point Forecast:
Dow IL
 39.02°N 90.3°W (Elev. 610 ft)
Last Update:
5:11 am CDT Oct 15, 2026
Forecast Valid:
8am CDT Oct 15, 2026-6pm CDT Oct 21, 2026
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation