Great Falls Weather Forecast

    • 51
    • 71

    Decreasing Clouds

    • 63
    • 83

    Mostly Sunny

    • 66
    • 88

    Slight Chance Thunderstorms

    • 69
    • 93

    Mostly Sunny

    • 72
    • 94

    Mostly Sunny

    • 66
    • 91

    Chance Thunderstorms

Today 15 May Central and Southeast Montgomery

Mostly sunny. Highs in the lower 70s. Northwest Winds around 10 Mph with Gusts up to 25 Mph.

Tonight 15 May Central and Southeast Montgomery

Partly cloudy in the Evening, then clearing. Lows in the lower 50s. West Winds 5 to 10 Mph.

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  • Temperature Real-Time

Great Falls Temperature Statistics

May Temperature

Washington/Dulles International Airport, DC (9.3 miles)

  • Lowest 8 May, 2026

    37.7 °F

  • Average May

    59.4 °F

  • Highest 5 May, 2026

    85.6 °F

Climate (2021–Present)

Washington/Dulles International Airport, DC (9.3 miles)

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  • Average Low 2021–2026

    47.6 °F

  • Average 2021–2026

    58.2 °F

  • Average High 2021–2026

    68.6 °F
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