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

51°F

11°C

Humidity 92%
Wind Speed Calm
Barometer 29.87 in (1011.5 mb)
Dewpoint 49°F (9°C)
Visibility 10.00 mi
Last update 15 Apr 5:56 am EDT
Extended Forecast for

South Lyme CT

  • Today

    Today: A slight chance of showers between 2pm and 5pm, then a slight chance of showers and thunderstorms after 5pm. Patchy fog between 7am and 8am. Otherwise, mostly sunny, with a high near 75. Calm wind becoming south 5 to 7 mph in the afternoon. Chance of precipitation is 20%.

    High: 75 °F

    Patchy Fog
    then Slight
    Chance
    T-storms

  • Tonight

    Tonight: A chance of showers and thunderstorms. Mostly cloudy, with a low around 53. Light and variable wind. Chance of precipitation is 50%.

    Low: 53 °F

    Chance
    T-storms

  • Thursday

    Thursday: Partly sunny, with a high near 73. Calm wind becoming south 5 to 7 mph in the afternoon.

    High: 73 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of showers. Mostly cloudy, with a low around 53. Light southwest wind.

    Low: 53 °F

    Slight Chance
    Showers

  • Friday

    Friday: A chance of showers, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 73. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 50%.

    High: 73 °F

    Chance
    Showers

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 51.

    Low: 51 °F

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 62.

    High: 62 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 47.

    Low: 47 °F

    Mostly Cloudy

  • Sunday

    Sunday: A 50 percent chance of showers after 8am. Mostly cloudy, with a high near 60.

    High: 60 °F

    Chance
    Showers

Detailed Forecast

Today
A slight chance of showers between 2pm and 5pm, then a slight chance of showers and thunderstorms after 5pm. Patchy fog between 7am and 8am. Otherwise, mostly sunny, with a high near 75. Calm wind becoming south 5 to 7 mph in the afternoon. Chance of precipitation is 20%.
Tonight
A chance of showers and thunderstorms. Mostly cloudy, with a low around 53. Light and variable wind. Chance of precipitation is 50%.
Thursday
Partly sunny, with a high near 73. Calm wind becoming south 5 to 7 mph in the afternoon.
Thursday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 53. Light southwest wind.
Friday
A chance of showers, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 73. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 50%.
Friday Night
Mostly cloudy, with a low around 51.
Saturday
Partly sunny, with a high near 62.
Saturday Night
Mostly cloudy, with a low around 47.
Sunday
A 50 percent chance of showers after 8am. Mostly cloudy, with a high near 60.
Sunday Night
A chance of rain showers before 5am, then a chance of rain and snow showers. Mostly cloudy, with a low around 39. Chance of precipitation is 50%.
Monday
A 30 percent chance of snow showers. Mostly sunny, with a high near 51.
Monday Night
Mostly clear, with a low around 33.
Tuesday
Sunny, with a high near 53.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
South Lyme CT
 41.32°N 72.29°W (Elev. 98 ft)
Last Update:
5:23 am EDT Apr 15, 2026
Forecast Valid:
6am EDT Apr 15, 2026-6pm EDT Apr 21, 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