Great Falls Weather Forecast

    • 58
    • 79

    Becoming Sunny

    • 63
    • 84

    Mostly Sunny

    • 68
    • 87

    Mostly Sunny

    • 66
    • 87

    Chance Rain Showers

    • 68
    • 83

    Partly Sunny

    • 66
    • 86

    Chance Rain Showers

Today 15 Sep Central and Southeast Montgomery

Sunny. Highs in the upper 70s. East Winds around 5 Mph, becoming southeast in the afternoon.

Tonight 15 Sep Central and Southeast Montgomery

Mostly clear. Lows in the upper 50s. Southeast Winds around 5 Mph.

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  • Temperature Real-Time

Great Falls Temperature Statistics

September Temperature

Washington/Dulles International Airport, DC (9.3 miles)

  • Lowest 8 September, 2026

    57.7 °F

  • Average September

    77.2 °F

  • Highest 1 September, 2026

    94.6 °F

Climate (2021–2026)

Washington/Dulles International Airport, DC (9.3 miles)

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  • Average Low 2021–2026

    47.6 °F

  • Average 2021–2026

    58.3 °F

  • Average High 2021–2026

    68.6 °F
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