Dangerous Heat and Possible Flooding
Dangerous heat will persist across the Southwest U.S. through Saturday with daytime highs of 110-115°F. Extreme Heat Warnings remain in effect. Dangerous heat will build across the southern Plains again beginning this weekend. Heavy to excessive rain over the Carolinas Friday may lead to isolated areas of flash flooding. Read More >
Current conditions at
St. Charles, St. Charles County Smartt Airport (KSET)
Lat: 38.93°NLon: 90.43°WElev: 436ft.
Fair
84°F
29°C
| Humidity | 44% |
| Wind Speed | E 5 mph |
| Barometer | 30.08 in (1018.3 mb) |
| Dewpoint | 60°F (16°C) |
| Visibility | 10.00 mi |
| Heat Index | 84°F (29°C) |
| Last update | 28 Aug 5:54 pm CDT |
Extended Forecast for
Grafton IL
Tonight
Low: 63 °F
Mostly Clear
Saturday
High: 88 °F
Mostly Sunny
Saturday Night
Low: 71 °F
Partly Cloudy
Sunday
High: 94 °F
Sunny
Sunday Night
Low: 75 °F
Mostly Clear
Monday
High: 97 °F
Hot
Monday Night
Low: 77 °F
Mostly Clear
Tuesday
High: 98 °F
Hot
Tuesday Night
Low: 78 °F
Mostly Clear
Detailed Forecast
Tonight
Mostly clear, with a low around 63. Light and variable wind.
Saturday
Mostly sunny, with a high near 88. South wind 3 to 8 mph.
Saturday Night
Partly cloudy, with a low around 71. South wind around 8 mph.
Sunday
Sunny, with a high near 94. South wind 7 to 11 mph.
Sunday Night
Mostly clear, with a low around 75. South wind 7 to 9 mph.
Monday
Sunny and hot, with a high near 97.
Monday Night
Mostly clear, with a low around 77.
Tuesday
Sunny and hot, with a high near 98.
Tuesday Night
Mostly clear, with a low around 78.
Wednesday
Sunny and hot, with a high near 97.
Wednesday Night
Mostly clear, with a low around 78.
Thursday
Sunny and hot, with a high near 97.
Thursday Night
Partly cloudy, with a low around 77.
Friday
Mostly sunny, with a high near 96.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Grafton IL
38.98°N 90.42°W (Elev. 673 ft)
38.98°N 90.42°W (Elev. 673 ft)
5:26 pm CDT Aug 28, 2026
6pm CDT Aug 28, 2026-6pm CDT Sep 4, 2026
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