Isle Royale Weather Forecast

    • 58
    • 71

    Decreasing Clouds

    • 61
    • 70

    Increasing Clouds

    • 63
    • 72

    Slight Chance Rain Showers

    • 62
    • 73

    Chance Thunderstorms

    • 64
    • 78

    Chance Rain Showers

    • 63
    • 81

    Partly Sunny

    • 62
    • 80

    Mostly Cloudy

Today 27 Aug Keweenaw

Partly cloudy with a 20 percent chance of Showers. Northwest Winds 5 to 10 Mph.

Tonight 27 Aug Keweenaw

Mostly clear. Lows in the mid 50s. Light north Winds.

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  • Temperature Real-Time

Isle Royale Temperature Statistics

August Temperature

Copper Harbor (58.4 miles)

  • Lowest 25 August, 2026

    52 °F

  • Average August

    63.6 °F

  • Highest 6 August, 2026

    81 °F

Climate (2021–2026)

Copper Harbor (58.4 miles)

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  • Average Low 2021–2026

    38.2 °F

  • Average 2021–2026

    44.4 °F

  • Average High 2021–2026

    50.5 °F
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