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 Downtown Airport (KCPS)
Lat: 38.56°NLon: 90.15°WElev: 410ft.
Fair
67°F
19°C
| Humidity | 87% |
| Wind Speed | Calm |
| Barometer | 30.12 in (1019.5 mb) |
| Dewpoint | 63°F (17°C) |
| Visibility | 10.00 mi |
| Last update | 28 Aug 9:53 pm CDT |
Extended Forecast for
Arnold MO
Tonight
Low: 62 °F
Mostly Clear
Saturday
High: 90 °F
Mostly Sunny
Saturday Night
Low: 68 °F
Decreasing
CloudsSunday
High: 95 °F
Sunny
Sunday Night
Low: 74 °F
Mostly Clear
Monday
High: 99 °F
Hot
Monday Night
Low: 76 °F
Mostly Clear
Tuesday
High: 99 °F
Hot
Tuesday Night
Low: 77 °F
Mostly Clear
Detailed Forecast
Tonight
Mostly clear, with a low around 62. Calm wind.
Saturday
Mostly sunny, with a high near 90. Calm wind becoming southeast around 6 mph in the afternoon.
Saturday Night
Mostly cloudy, then gradually becoming clear, with a low around 68. South wind 3 to 5 mph.
Sunday
Sunny, with a high near 95. South wind 5 to 8 mph.
Sunday Night
Mostly clear, with a low around 74. South wind around 7 mph.
Monday
Sunny and hot, with a high near 99.
Monday Night
Mostly clear, with a low around 76.
Tuesday
Sunny and hot, with a high near 99.
Tuesday Night
Mostly clear, with a low around 77.
Wednesday
Sunny and hot, with a high near 99.
Wednesday Night
Mostly clear, with a low around 78.
Thursday
Sunny and hot, with a high near 98.
Thursday Night
Partly cloudy, with a low around 77.
Friday
Mostly sunny and hot, with a high near 97.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Arnold MO
38.42°N 90.38°W (Elev. 495 ft)
38.42°N 90.38°W (Elev. 495 ft)
9:21 pm CDT Aug 28, 2026
10pm CDT Aug 28, 2026-6pm CDT Sep 4, 2026
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