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 | Calm |
| Barometer | 30.11 in (1019.0 mb) |
| Dewpoint | 62°F (17°C) |
| Visibility | 10.00 mi |
| Last update | 28 Aug 11:54 pm CDT |
Extended Forecast for
O'Fallon MO
Overnight
Low: 62 °F
Mostly Clear
Saturday
High: 88 °F
Mostly Sunny
Saturday Night
Low: 69 °F
Partly Cloudy
Sunday
High: 94 °F
Mostly Sunny
Sunday Night
Low: 75 °F
Mostly Clear
Monday
High: 97 °F
Hot
Monday Night
Low: 77 °F
Mostly Clear
Tuesday
High: 97 °F
Hot
Tuesday Night
Low: 78 °F
Mostly Clear
Detailed Forecast
Overnight
Mostly clear, with a low around 62. Calm wind.
Saturday
Mostly sunny, with a high near 88. Calm wind becoming south around 6 mph in the afternoon.
Saturday Night
Partly cloudy, with a low around 69. South wind 5 to 7 mph.
Sunday
Mostly sunny, with a high near 94. South wind 6 to 8 mph.
Sunday Night
Mostly clear, with a low around 75. South wind 5 to 7 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 97.
Tuesday Night
Mostly clear, with a low around 78.
Wednesday
Mostly sunny, with a high near 96.
Wednesday Night
Mostly clear, with a low around 78.
Thursday
Sunny, with a high near 96.
Thursday Night
Partly cloudy, with a low around 77.
Friday
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)
11:26 pm CDT Aug 28, 2026
12am CDT Aug 29, 2026-6pm CDT Sep 4, 2026
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