Great Falls Weather Forecast

    • 50
    • 77

    Mostly Cloudy

    • 42
    • 66

    Chance Rain Showers

    • 54
    • 83

    Partly Sunny

    • 44
    • 77

    Partly Sunny

    • 53
    • 82

    Partly Sunny

    • 51
    • 81

    Mostly Sunny

Today 8 May Cascade County below 5000ft

Warmer. Sunny until late afternoon then becoming partly sunny. Highs 72 to 78. West Winds 5 to 15 Mph.

Tonight 8 May Cascade County below 5000ft

Mostly cloudy. Slight chance of Thunderstorms in the Evening, then slight chance of rain Showers after midnight. Lows in the upper 40s. West Winds 5 to 15 Mph. Chance of precipitation 20 percent.

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  • Temperature Real-Time

Great Falls Temperature Statistics

May Temperature

Great Falls, Great Falls International Airport (3.7 miles)

  • Lowest 5 May, 2026

    33.1 °F

  • Average May

    49.9 °F

  • Highest 3 May, 2026

    76.6 °F

Climate (2021–Present)

Great Falls, Great Falls International Airport (3.7 miles)

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  • Average Low 2021–2026

    34.4 °F

  • Average 2021–2026

    47 °F

  • Average High 2021–2026

    59.1 °F
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