Big Sky Weather Forecast

    • 25
    • 35

    Mostly Sunny

    • 28
    • 46

    Mostly Sunny

    • 33
    • 53

    Mostly Sunny

    • 32
    • 52

    Mostly Sunny

    • 36
    • 51

    Partly Sunny

    • 27
    • 44

    Snow Likely

    • 20
    • 35

    Snow Likely

Today 20 Oct Gallatin and Madison County Mountains and Centennial Mountains

Mostly cloudy with a 20 percent chance of snow late in the Morning, then sunny in the afternoon. Highs 30 to 40. West Winds 10 to 20 Mph.

Tonight 20 Oct Gallatin and Madison County Mountains and Centennial Mountains

Mostly clear. Near steady temperature in the upper 20s. Southwest Winds 5 to 15 Mph.

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Big Sky Temperature Statistics

October Temperature

Ennis - Big Sky Airport (13.7 miles)

  • Lowest 6 October, 2025

    23 °F

  • Average October

    45.3 °F

  • Highest 10 October, 2025

    71.6 °F

Climate (2020–Present)

Ennis - Big Sky Airport (13.7 miles)

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  • Average Low 2020–2025

    31.3 °F

  • Average 2020–2025

    43.7 °F

  • Average High 2020–2025

    55.6 °F
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