Fairmont City Weather Forecast
- 76
- 95
Becoming Sunny
- 75
- 95
Mostly Sunny
- 74
- 94
Partly Sunny
- 73
- 94
Chance Thunderstorms
- 72
- 92
Chance Thunderstorms
- 72
- 91
Chance Thunderstorms
Today 8 Aug St. Clair
Sunny. Highs in the mid 90s. South Winds 5 to 10 Mph. Heat index Values up to 101.
Tonight 8 Aug St. Clair
Mostly clear. Lows in the mid 70s. South Winds 10 to 15 Mph.
Fairmont City Temperature Statistics
August Temperature
St. Louis Downtown Airport (6.2 miles)
Lowest 3 August, 2025
56.6 °FAverage August
72.7 °FHighest 5 August, 2025
87.1 °F
Climate (2020–Present)
St. Louis Downtown Airport (6.2 miles)
Average Low 2020–2025
47.3 °FAverage 2020–2025
57.8 °FAverage High 2020–2025
68.4 °F