National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Groton / New London, Groton / New London Airport (KGON)

Lat: 41.33°NLon: 72.05°WElev: 10ft.

Fair

52°F

11°C

Humidity 89%
Wind Speed E 3 mph
Barometer 30.15 in (1021.0 mb)
Dewpoint 49°F (9°C)
Visibility 10.00 mi
Last update 15 Oct 7:56 am EDT
Extended Forecast for

Old Lyme CT

  • Today

    Today: Sunny, with a high near 63. North wind 5 to 9 mph becoming light northeast in the afternoon.

    High: 63 °F

    Sunny

  • Tonight

    Tonight: A 30 percent chance of showers, mainly after 5am. Increasing clouds, with a low around 48. Calm wind becoming southeast around 6 mph after midnight.

    Low: 48 °F

    Partly Cloudy
    then Chance
    Showers

  • Friday

    Friday: Showers before 2pm, then a chance of showers and thunderstorms after 5pm. High near 70. Southwest wind 9 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 70 °F

    Showers

  • Friday Night

    Friday Night: Showers and thunderstorms. Low around 41. Southwest wind 6 to 9 mph becoming northwest after midnight. Winds could gust as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 41 °F

    Showers

  • Saturday

    Saturday: A 30 percent chance of showers before 8am. Mostly cloudy, then gradually becoming sunny, with a high near 54. North wind around 14 mph, with gusts as high as 26 mph.

    High: 54 °F

    Chance
    Showers then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 35.

    Low: 35 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 57.

    High: 57 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 61.

    High: 61 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 63. North wind 5 to 9 mph becoming light northeast in the afternoon.
Tonight
A 30 percent chance of showers, mainly after 5am. Increasing clouds, with a low around 48. Calm wind becoming southeast around 6 mph after midnight.
Friday
Showers before 2pm, then a chance of showers and thunderstorms after 5pm. High near 70. Southwest wind 9 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Friday Night
Showers and thunderstorms. Low around 41. Southwest wind 6 to 9 mph becoming northwest after midnight. Winds could gust as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Saturday
A 30 percent chance of showers before 8am. Mostly cloudy, then gradually becoming sunny, with a high near 54. North wind around 14 mph, with gusts as high as 26 mph.
Saturday Night
Mostly clear, with a low around 35.
Sunday
Sunny, with a high near 57.
Sunday Night
Mostly clear, with a low around 39.
Monday
Sunny, with a high near 61.
Monday Night
Partly cloudy, with a low around 42.
Tuesday
Mostly sunny, with a high near 64.
Tuesday Night
Partly cloudy, with a low around 42.
Wednesday
Sunny, with a high near 63.
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ABOUT THIS FORECAST

 
Point Forecast:
Old Lyme CT
 41.31°N 72.33°W (Elev. 43 ft)
Last Update:
7:44 am EDT Oct 15, 2026
Forecast Valid:
8am EDT Oct 15, 2026-6pm EDT Oct 21, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation