Lake Sunapee Weather Forecast

    • 35
    • 42

    Rain Likely

    • 24
    • 54

    Rain

    • 30
    • 33

    Slight Chance Snow

    • 17
    • 38

    Mostly Cloudy

    • 15
    • 23

    Partly Sunny

    • 25
    • 31

    Chance Snow

    • 17
    • 31

    Partly Sunny

Today 18 Dec Sullivan

Partly sunny. Highs in the lower 40s. South Winds around 10 Mph.

Tonight 18 Dec Sullivan

Cloudy. Areas of fog. Rain likely after midnight. Lows in the lower 30s. Temperatures rising into the mid 40s after midnight. South Winds 10 to 15 Mph with Gusts up to 30 Mph. Chance of rain 70 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Lake Sunapee Temperature Statistics

December Temperature

Lebanon Municipal Airport (21.1 miles)

  • Lowest 9 December, 2025

    -8 °F

  • Average December

    22.3 °F

  • Highest 11 December, 2025

    39 °F

Climate (2020–Present)

Lebanon Municipal Airport (21.1 miles)

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  • Average Low 2020–2025

    38.1 °F

  • Average 2020–2025

    48.8 °F

  • Average High 2020–2025

    59.8 °F
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