Decatur Island - Decatur Head Weather Forecast

    • 53
    • 69

    Mostly Sunny

    • 53
    • 65

    Partly Sunny

    • 52
    • 64

    Partly Sunny

    • 53
    • 64

    Mostly Cloudy

    • 54
    • 65

    Partly Sunny

    • 54
    • 67

    Partly Sunny

    • 54
    • 67

    Mostly Sunny

Today 17 Jul San Juan County

Sunny. Highs in the 70s. Light wind.

Tonight 17 Jul San Juan County

Mostly clear. Lows in the 50s to lower 60s. Southwest wind to 10 Mph in the evening becoming light.

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Decatur Island - Decatur Head Temperature Statistics

July Temperature

Friday Harbor Airport (10.6 miles)

  • Lowest 4 July, 2025

    46.7 °F

  • Average July

    61.4 °F

  • Highest 15 July, 2025

    87.1 °F

Climate (2020–Present)

Friday Harbor Airport (10.6 miles)

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  • Average Low 2020–2025

    44.3 °F

  • Average 2020–2025

    51.7 °F

  • Average High 2020–2025

    59.5 °F
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