Island Mountain Weather Forecast

    • 42
    • 59

    Increasing Clouds

    • 41
    • 61

    Mostly Sunny

    • 42
    • 63

    Mostly Sunny

    • 41
    • 61

    Partly Sunny

    • 39
    • 57

    Partly Sunny

    • 36
    • 52

    Slight Chance Rain

Today 17 Jan Northeastern Mendocino Interior

Sunny. Highs 57 to 72.

Tonight 17 Jan Northeastern Mendocino Interior

Mostly cloudy. Lows 38 to 48.

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Island Mountain Temperature Statistics

January Temperature

Fortuna Rohnerville Airport (52.8 miles)

  • Lowest 9 January, 2026

    32 °F

  • Average January

    45.8 °F

  • Highest 13 January, 2026

    60.8 °F

Climate (2021–Present)

Fortuna Rohnerville Airport (52.8 miles)

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  • Average Low 2021–2026

    45.1 °F

  • Average 2021–2026

    51.2 °F

  • Average High 2021–2026

    59.4 °F
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