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

56°F

13°C

Humidity 72%
Wind Speed SE 13 mph
Barometer 29.80 in (1009.1 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Last update 17 Feb 12:54 pm CST
Extended Forecast for

Hardin ILSimilar City Names

  • This Afternoon

    This Afternoon: Mostly cloudy, with a high near 63. South wind 13 to 15 mph, with gusts as high as 24 mph.

    High: 63 °F

    Mostly Cloudy

  • Tonight

    Tonight: A slight chance of showers between 11pm and 3am. Cloudy, then gradually becoming partly cloudy, with a low around 54. South wind 11 to 17 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.

    Low: 54 °F

    Slight Chance
    Showers

  • Wednesday

    Wednesday: Sunny, with a high near 70. West wind 7 to 13 mph, with gusts as high as 22 mph.

    High: 70 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Clear during the early evening, then becoming mostly cloudy, with a low around 47. South wind 3 to 6 mph.

    Low: 47 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 40 percent chance of rain. Mostly sunny, with a high near 71. Southeast wind 6 to 14 mph becoming southwest in the afternoon. Winds could gust as high as 24 mph.

    High: 71 °F

    Chance Rain

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 34.

    Low: 34 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 48.

    High: 48 °F

    Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 29.

    Low: 29 °F

    Partly Cloudy

  • Saturday

    Saturday: A 40 percent chance of snow, mainly after noon. Mostly sunny, with a high near 41.

    High: 41 °F

    Chance Snow

Detailed Forecast

This Afternoon
Mostly cloudy, with a high near 63. South wind 13 to 15 mph, with gusts as high as 24 mph.
Tonight
A slight chance of showers between 11pm and 3am. Cloudy, then gradually becoming partly cloudy, with a low around 54. South wind 11 to 17 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.
Wednesday
Sunny, with a high near 70. West wind 7 to 13 mph, with gusts as high as 22 mph.
Wednesday Night
Clear during the early evening, then becoming mostly cloudy, with a low around 47. South wind 3 to 6 mph.
Thursday
A 40 percent chance of rain. Mostly sunny, with a high near 71. Southeast wind 6 to 14 mph becoming southwest in the afternoon. Winds could gust as high as 24 mph.
Thursday Night
Mostly clear, with a low around 34.
Friday
Sunny, with a high near 48.
Friday Night
Partly cloudy, with a low around 29.
Saturday
A 40 percent chance of snow, mainly after noon. Mostly sunny, with a high near 41.
Saturday Night
A 30 percent chance of snow, mainly before midnight. Partly cloudy, with a low around 24.
Sunday
A 20 percent chance of snow. Mostly sunny, with a high near 37.
Sunday Night
Mostly clear, with a low around 18.
Monday
Sunny, with a high near 37.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Hardin ILSimilar City Names
 39.14°N 90.61°W (Elev. 427 ft)
Last Update:
12:26 pm CST Feb 17, 2026
Forecast Valid:
1pm CST Feb 17, 2026-6pm CST Feb 23, 2026
 
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