Henderson Lake Weather Forecast

    • 55
    • 71

    Rain Likely

    • 54
    • 69

    Chance Rain

    • 55
    • 70

    Mostly Cloudy

    • 54
    • 69

    Mostly Cloudy

    • 53
    • 69

    Mostly Sunny

    • 54
    • 71

    Mostly Sunny

    • 55
    • 72

    Sunny

Today 16 Aug San Juan County

Mostly cloudy with a chance of rain until late Afternoon, then mostly cloudy with rain likely late in the afternoon. Rainfall Amounts less than a tenth of an inch likely. Highs in the upper 60s to mid 70s. South wind to 10 Mph.

Tonight 16 Aug San Juan County

Mostly cloudy with a chance of Showers. Lows in the 50s. Southwest wind to 10 Mph in the evening becoming light.

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Henderson Lake Temperature Statistics

August Temperature

Friday Harbor Airport (9.3 miles)

  • Lowest 8 August, 2025

    47.6 °F

  • Average August

    63.4 °F

  • Highest 12 August, 2025

    90.6 °F

Climate (2020–Present)

Friday Harbor Airport (9.3 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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