Fairmont City Weather Forecast

    • 65
    • 87

    Increasing Clouds

    • 74
    • 87

    Mostly Sunny

    • 72
    • 99

    Chance Thunderstorms

    • 74
    • 95

    Slight Chance Thunderstorms

    • 71
    • 95

    Chance Thunderstorms

    • 66
    • 90

    Chance Rain Showers

Today 13 Sep St. Clair

Sunny. Near steady temperature in the mid 80s. North Winds 5 to 10 Mph with Gusts up to 20 Mph.

Tonight 13 Sep St. Clair

Partly cloudy. Lows in the mid 60s. Northeast Winds 5 to 10 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Fairmont City Temperature Statistics

September Temperature

St. Louis Downtown Airport (6.2 miles)

  • Lowest 8 September, 2026

    59.6 °F

  • Average September

    82.2 °F

  • Highest 5 September, 2026

    102.7 °F

Climate (2021–2026)

St. Louis Downtown Airport (6.2 miles)

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  • Average Low 2021–2026

    47.7 °F

  • Average 2021–2026

    58.6 °F

  • Average High 2021–2026

    69.4 °F
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