Griswold Island Weather Forecast

    • 58
    • 69

    Rain Showers

    • 60
    • 71

    Mostly Cloudy

    • 59
    • 77

    Partly Sunny

    • 54
    • 70

    Chance Rain Showers

    • 54
    • 67

    Partly Sunny

    • 53
    • 67

    Partly Sunny

Today 25 May Southern New London

Areas of fog in the morning. Showers with a slight chance of Thunderstorms. Highs around 70. South Winds around 5 Mph, becoming southwest in the afternoon. Chance of rain near 100 percent.

Tonight 25 May Southern New London

Mostly cloudy. Lows in the upper 50s. West Winds around 5 Mph in the Evening, becoming light and variable.

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Griswold Island Temperature Statistics

May Temperature

Groton / New London, Groton / New London Airport (9.3 miles)

  • Lowest 4 May, 2026

    37 °F

  • Average May

    55.8 °F

  • Highest 20 May, 2026

    84 °F

Climate (2021–Present)

Groton / New London, Groton / New London Airport (9.3 miles)

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  • Average Low 2021–2026

    45.3 °F

  • Average 2021–2026

    53.2 °F

  • Average High 2021–2026

    60.7 °F
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