Thunder Arm Weather Forecast

    • 50
    • 73

    Sunny

    • 51
    • 76

    Sunny

    • 51
    • 73

    Mostly Sunny

    • 51
    • 74

    Mostly Sunny

    • 51
    • 75

    Mostly Sunny

    • 50
    • 70

    Partly Sunny

    • 49
    • 67

    Chance Rain

Today 16 Sep Foothills and Valleys of the North Cascades

Sunny. Highs in the 70s to lower 80s. Light wind.

Tonight 16 Sep Foothills and Valleys of the North Cascades

Clear. Lows in the upper 40s to mid 50s. Light wind becoming north to 10 Mph after midnight.

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  • Temperature Real-Time

Thunder Arm Temperature Statistics

September Temperature

Arlington Municipal Airport (60.9 miles)

  • Lowest 8 September, 2026

    46 °F

  • Average September

    60.1 °F

  • Highest 9 September, 2026

    78.1 °F

Climate (2021–2026)

Arlington Municipal Airport (60.9 miles)

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  • Average Low 2021–2026

    42.6 °F

  • Average 2021–2026

    50.9 °F

  • Average High 2021–2026

    59.9 °F
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