Big Arm Weather Forecast

    • 47
    • 72

    Decreasing Clouds

    • 42
    • 57

    Partly Sunny

    • 45
    • 59

    Mostly Cloudy

    • 45
    • 61

    Partly Sunny

    • 47
    • 59

    Partly Sunny

    • 46
    • 60

    Partly Sunny

Today 25 Sep Flathead/Mission Valleys

Mostly cloudy. A 20 percent chance of rain in the afternoon. Highs in the 70s. Windy with southwest Winds 20 to 30 Mph with Gusts to around 40 Mph.

Tonight 25 Sep Flathead/Mission Valleys

Mostly cloudy. A 50 percent chance of rain in the evening. Lows in the upper 30s to mid 40s. Southwest Winds to 15 Mph with Gusts to around 35 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Big Arm Temperature Statistics

September Temperature

Kalispell, Glacier Park International Airport (34.8 miles)

  • Lowest 17 September, 2026

    38.6 °F

  • Average September

    56.9 °F

  • Highest 1 September, 2026

    84.7 °F

Climate (2021–2026)

Kalispell, Glacier Park International Airport (34.8 miles)

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  • Average Low 2021–2026

    33.4 °F

  • Average 2021–2026

    45.4 °F

  • Average High 2021–2026

    57 °F
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