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

56°F

13°C

Humidity 70%
Wind Speed N 6 mph
Barometer 30.42 in (1030.2 mb)
Dewpoint 46°F (8°C)
Visibility 10.00 mi
Last update 10 Oct 8:56 am EDT
Extended Forecast for

Old Lyme CT

  • Today

    Today: Mostly sunny, with a high near 65. Light and variable wind becoming north around 5 mph.

    High: 65 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 49. Calm wind.

    Low: 49 °F

    Partly Cloudy

  • Sunday

    Sunday: Rain after 2pm. High near 65. Southeast wind 5 to 9 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 65 °F

    Mostly Cloudy
    then Rain

  • Sunday Night

    Sunday Night: Rain, with thunderstorms also possible after 11pm. Low around 56. East wind around 9 mph, with gusts as high as 23 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

    Low: 56 °F

    Rain

  • Columbus Day

    Columbus Day: Rain likely, mainly before 8am. Cloudy through mid morning, then gradual clearing, with a high near 69. North wind 7 to 9 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    High: 69 °F

    Rain Likely
    then Slight
    Chance Rain

  • Monday Night

    Monday Night: Mostly clear, with a low around 53.

    Low: 53 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 50 percent chance of showers after 2pm. Partly sunny, with a high near 68.

    High: 68 °F

    Mostly Sunny
    then Chance
    Showers

  • Tuesday Night

    Tuesday Night: Showers likely, mainly between 8pm and 2am. Mostly cloudy, with a low around 52. Chance of precipitation is 60%.

    Low: 52 °F

    Showers
    Likely

  • Wednesday

    Wednesday: A 30 percent chance of showers before 8am. Partly sunny, with a high near 64.

    High: 64 °F

    Chance
    Showers then
    Mostly Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 65. Light and variable wind becoming north around 5 mph.
Tonight
Partly cloudy, with a low around 49. Calm wind.
Sunday
Rain after 2pm. High near 65. Southeast wind 5 to 9 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.
Sunday Night
Rain, with thunderstorms also possible after 11pm. Low around 56. East wind around 9 mph, with gusts as high as 23 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
Columbus Day
Rain likely, mainly before 8am. Cloudy through mid morning, then gradual clearing, with a high near 69. North wind 7 to 9 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Monday Night
Mostly clear, with a low around 53.
Tuesday
A 50 percent chance of showers after 2pm. Partly sunny, with a high near 68.
Tuesday Night
Showers likely, mainly between 8pm and 2am. Mostly cloudy, with a low around 52. Chance of precipitation is 60%.
Wednesday
A 30 percent chance of showers before 8am. Partly sunny, with a high near 64.
Wednesday Night
Partly cloudy, with a low around 45.
Thursday
Sunny, with a high near 62.
Thursday Night
Partly cloudy, with a low around 46.
Friday
A 30 percent chance of showers. Partly sunny, with a high near 64.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Old Lyme CT
 41.31°N 72.33°W (Elev. 43 ft)
Last Update:
2:11 am EDT Oct 10, 2026
Forecast Valid:
9am EDT Oct 10, 2026-6pm EDT Oct 16, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

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