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. Louis, Spirit Of St. Louis Airport (KSUS)
Lat: 38.66°NLon: 90.66°WElev: 463ft.
Fair
64°F
18°C
| Humidity | 93% |
| Wind Speed | W 3 mph |
| Barometer | 30.05 in (1017.1 mb) |
| Dewpoint | 62°F (17°C) |
| Visibility | 10.00 mi |
| Last update | 27 Aug 10:54 pm CDT |
Extended Forecast for
O'Fallon MO
Tonight
Low: 63 °F
Clear
Friday
High: 86 °F
Sunny
Friday Night
Low: 63 °F
Partly Cloudy
Saturday
High: 88 °F
Mostly Sunny
Saturday Night
Low: 70 °F
Partly Cloudy
Sunday
High: 94 °F
Sunny
Sunday Night
Low: 75 °F
Mostly Clear
Monday
High: 96 °F
Mostly Sunny
Monday Night
Low: 77 °F
Mostly Clear
Detailed Forecast
Tonight
Clear, with a low around 63. Calm wind.
Friday
Sunny, with a high near 86. Calm wind.
Friday Night
Partly cloudy, with a low around 63. Calm wind.
Saturday
Mostly sunny, with a high near 88. Calm wind becoming south around 5 mph in the morning.
Saturday Night
Partly cloudy, with a low around 70. Southeast wind around 6 mph.
Sunday
Sunny, with a high near 94.
Sunday Night
Mostly clear, with a low around 75.
Monday
Mostly sunny, with a high near 96.
Monday Night
Mostly clear, with a low around 77.
Tuesday
Sunny, with a high near 96.
Tuesday Night
Mostly clear, with a low around 77.
Wednesday
Sunny, with a high near 95.
Wednesday Night
Mostly clear, with a low around 78.
Thursday
Mostly sunny, with a high near 95.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
O'Fallon MO
38.79°N 90.71°W (Elev. 535 ft)
38.79°N 90.71°W (Elev. 535 ft)
9:11 pm CDT Aug 27, 2026
11pm CDT Aug 27, 2026-6pm CDT Sep 3, 2026
Additional Resources
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