Sister Island Weather Forecast

    • 7
    • 20

    Increasing Clouds

    • 16
    • 24

    Blustery

    • 12
    • 31

    Partly Sunny

    • 14
    • 30

    Partly Sunny

    • 13
    • 30

    Partly Sunny

    • 11
    • 28

    Partly Sunny

    • 14
    • 26

    Chance Snow

Today 31 Jan Coastal Cumberland

Mostly sunny. Highs around 20. Northwest Winds around 10 Mph.

Tonight 31 Jan Coastal Cumberland

Mostly clear in the Evening, then becoming partly cloudy. Lows around 3 above. Light and variable Winds, becoming north around 10 Mph with Gusts up to 20 Mph after midnight. Wind chill Values as low as 10 below after midnight.

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Sister Island Temperature Statistics

January Temperature

Portland, Portland International Jetport (17.4 miles)

  • Lowest 25 January, 2026

    -5.4 °F
  • Average January

    22.8 °F
  • Highest 14 January, 2026

    48.7 °F

Climate (2021–Present)

Portland, Portland International Jetport (17.4 miles)

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  • Average Low 2021–2026

    40.3 °F
  • Average 2021–2026

    48.8 °F
  • Average High 2021–2026

    57.2 °F
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