Six Flags - St. Louis Weather Forecast
- 66
- 87
Decreasing Clouds
- 64
- 83
Mostly Sunny
- 64
- 86
Mostly Sunny
- 61
- 87
Mostly Sunny
- 56
- 81
Mostly Sunny
- 54
- 75
Partly Sunny
Today 20 Aug St. Louis
Mostly sunny. Highs in the upper 80s. Northeast Winds 5 to 10 Mph.
Tonight 20 Aug St. Louis
Mostly clear. Lows in the mid 60s. Northeast Winds 5 to 10 Mph.
Six Flags - St. Louis Temperature Statistics
August Temperature
St. Louis, Spirit Of St. Louis Airport (9.9 miles)
Lowest 3 August, 2025
55.7 °FAverage August
78.9 °FHighest 16 August, 2025
98.7 °F
Climate (2020–Present)
St. Louis, Spirit Of St. Louis Airport (9.9 miles)
Average Low 2020–2025
45.9 °FAverage 2020–2025
56.9 °FAverage High 2020–2025
68.1 °F