Big Arm Weather Forecast

    • 54
    • 73

    Mostly Sunny

    • 52
    • 73

    Decreasing Clouds

    • 53
    • 71

    Partly Sunny

    • 55
    • 73

    Mostly Cloudy

    • 48
    • 67

    Chance Rain

    • 45
    • 57

    Mostly Cloudy

    • 46
    • 58

    Mostly Cloudy

Today 21 Sep Flathead/Mission Valleys

Mostly cloudy. Highs in the upper 50s to mid 60s.

Tonight 21 Sep Flathead/Mission Valleys

Mostly clear. Lows in the mid 40s to lower 50s.

Graph Plots Open in Graphs

  • 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)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2021–2026

    33.4 °F

  • Average 2021–2026

    45.4 °F

  • Average High 2021–2026

    57 °F
Get WillyWeather+ to remove ads