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

Hazardous Weather Conditions

Current conditions at

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

Lat: 38.93°NLon: 90.43°WElev: 436ft.

Fair

83°F

28°C

Humidity 57%
Wind Speed SW 9 mph
Barometer 30.00 in (1015.5 mb)
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 20 Jun 10:54 am CDT
Extended Forecast for

2 Miles NNW Grafton IL

Extreme Heat Watch June 21, 12:00pm until June 24, 09:00pm
Click here for hazard details and duration
Extreme Heat Watch

  • Today

    Today: Mostly sunny, with a high near 90. South wind around 11 mph.

    High: 90 °F

    Mostly Sunny

  • Tonight

    Tonight: Clear, with a low around 76. South wind 9 to 11 mph, with gusts as high as 21 mph.

    Low: 76 °F

    Clear

  • Saturday

    Saturday: Sunny, with a high near 94. Heat index values as high as 102. Southwest wind 10 to 14 mph, with gusts as high as 24 mph.

    High: 94 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 76. South wind 9 to 11 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 94. Southwest wind 8 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 76.

    Low: 76 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 94.

    High: 94 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 76.

    Low: 76 °F

    Partly Cloudy

  • Tuesday

    Tuesday: A 20 percent chance of showers before 1pm. Mostly sunny, with a high near 93.

    High: 93 °F

    Slight Chance
    Showers

Detailed Forecast

Today
Mostly sunny, with a high near 90. South wind around 11 mph.
Tonight
Clear, with a low around 76. South wind 9 to 11 mph, with gusts as high as 21 mph.
Saturday
Sunny, with a high near 94. Heat index values as high as 102. Southwest wind 10 to 14 mph, with gusts as high as 24 mph.
Saturday Night
Mostly clear, with a low around 76. South wind 9 to 11 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 94. Southwest wind 8 to 10 mph, with gusts as high as 20 mph.
Sunday Night
Mostly clear, with a low around 76.
Monday
Sunny, with a high near 94.
Monday Night
Partly cloudy, with a low around 76.
Tuesday
A 20 percent chance of showers before 1pm. Mostly sunny, with a high near 93.
Tuesday Night
Partly cloudy, with a low around 76.
Wednesday
A 20 percent chance of showers and thunderstorms. Sunny, with a high near 92.
Wednesday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 90.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles NNW Grafton IL
 39°N 90.44°W (Elev. 774 ft)
Last Update:
8:22 am CDT Jun 20, 2025
Forecast Valid:
11am CDT Jun 20, 2025-6pm CDT Jun 26, 2025
 
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