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Hazardous Weather Conditions

Current conditions at

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

Lat: 38.93°NLon: 90.43°WElev: 436ft.

Fair

48°F

9°C

Humidity 83%
Wind Speed NE 5 mph
Barometer 30.09 in (1018.7 mb)
Dewpoint 43°F (6°C)
Visibility 10.00 mi
Wind Chill46°F (8°C)
Last update 14 May 4:54 am CDT
Extended Forecast for

2 Miles NNW Grafton IL

  • Today

    Today: Patchy fog before 7am. Otherwise, sunny, with a high near 74. South wind 3 to 8 mph.

    High: 74 °F

    Patchy Fog
    then Sunny

  • Tonight

    Tonight: A chance of showers and thunderstorms between 2am and 5am, then showers likely and possibly a thunderstorm after 5am. Increasing clouds, with a low around 56. Southeast wind 10 to 13 mph, with gusts as high as 21 mph. Chance of precipitation is 60%.

    Low: 56 °F

    Partly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers and thunderstorms likely before 1pm, then a slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Cloudy through mid morning, then gradual clearing, with a high near 82. South wind 11 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%.

    High: 82 °F

    Showers
    Likely then
    Slight Chance
    T-storms

  • Friday Night

    Friday Night: A slight chance of thunderstorms before 7pm, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 65. South wind 8 to 10 mph. Chance of precipitation is 40%.

    Low: 65 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Saturday

    Saturday: Showers likely and possibly a thunderstorm. Partly sunny, with a high near 82. Southwest wind 8 to 10 mph, with gusts as high as 21 mph. Chance of precipitation is 70%.

    High: 82 °F

    Showers
    Likely

  • Saturday Night

    Saturday Night: A 30 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 64.

    Low: 64 °F

    Chance
    T-storms

  • Sunday

    Sunday: Mostly sunny, with a high near 88.

    High: 88 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 70.

    Low: 70 °F

    Mostly Clear

  • Monday

    Monday: A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 87.

    High: 87 °F

    Sunny then
    Chance
    T-storms

Detailed Forecast

Today
Patchy fog before 7am. Otherwise, sunny, with a high near 74. South wind 3 to 8 mph.
Tonight
A chance of showers and thunderstorms between 2am and 5am, then showers likely and possibly a thunderstorm after 5am. Increasing clouds, with a low around 56. Southeast wind 10 to 13 mph, with gusts as high as 21 mph. Chance of precipitation is 60%.
Friday
Showers and thunderstorms likely before 1pm, then a slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Cloudy through mid morning, then gradual clearing, with a high near 82. South wind 11 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%.
Friday Night
A slight chance of thunderstorms before 7pm, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 65. South wind 8 to 10 mph. Chance of precipitation is 40%.
Saturday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 82. Southwest wind 8 to 10 mph, with gusts as high as 21 mph. Chance of precipitation is 70%.
Saturday Night
A 30 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 64.
Sunday
Mostly sunny, with a high near 88.
Sunday Night
Mostly clear, with a low around 70.
Monday
A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 87.
Monday Night
Showers likely and possibly a thunderstorm before 1am, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 68. Chance of precipitation is 60%.
Tuesday
Showers and thunderstorms likely. Partly sunny, with a high near 79. Chance of precipitation is 70%.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 61. Chance of precipitation is 60%.
Wednesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 75.
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ABOUT THIS FORECAST

 
Point Forecast:
2 Miles NNW Grafton IL
 39°N 90.44°W (Elev. 774 ft)
Last Update:
5:21 am CDT May 14, 2026
Forecast Valid:
5am CDT May 14, 2026-6pm CDT May 20, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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