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

49°F

9°C

Humidity 74%
Wind Speed SW 6 mph
Barometer 30.12 in (1019.9 mb)
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Wind Chill46°F (8°C)
Last update 13 May 12:56 am EDT
Extended Forecast for

Old Lyme CT

  • Overnight

    Overnight: Partly cloudy, with a low around 49. Southwest wind around 5 mph.

    Low: 49 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 65. South wind 5 to 10 mph increasing to 12 to 17 mph in the afternoon. Winds could gust as high as 30 mph.

    High: 65 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A slight chance of showers before 11pm, then a chance of showers after 2am. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 52. South wind 5 to 10 mph becoming light after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 40%.

    Low: 52 °F

    Chance
    Showers and
    Patchy Fog

  • Thursday

    Thursday: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 8am. Patchy fog. High near 65. Southeast wind 3 to 7 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 65 °F

    Showers and
    Patchy Fog

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 50. Calm wind. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 50 °F

    Showers
    Likely

  • Friday

    Friday: A 50 percent chance of showers. Mostly cloudy, with a high near 67.

    High: 67 °F

    Chance
    Showers

  • Friday Night

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

    Low: 51 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 75.

    High: 75 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 56.

    Low: 56 °F

    Mostly Clear

Detailed Forecast

Overnight
Partly cloudy, with a low around 49. Southwest wind around 5 mph.
Wednesday
Mostly cloudy, with a high near 65. South wind 5 to 10 mph increasing to 12 to 17 mph in the afternoon. Winds could gust as high as 30 mph.
Wednesday Night
A slight chance of showers before 11pm, then a chance of showers after 2am. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 52. South wind 5 to 10 mph becoming light after midnight. Winds could gust as high as 24 mph. Chance of precipitation is 40%.
Thursday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 8am. Patchy fog. High near 65. Southeast wind 3 to 7 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 50. Calm wind. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Friday
A 50 percent chance of showers. Mostly cloudy, with a high near 67.
Friday Night
Partly cloudy, with a low around 51.
Saturday
Sunny, with a high near 75.
Saturday Night
Mostly clear, with a low around 56.
Sunday
Sunny, with a high near 81.
Sunday Night
Mostly clear, with a low around 56.
Monday
Mostly sunny, with a high near 76.
Monday Night
Partly cloudy, with a low around 56.
Tuesday
Partly sunny, with a high near 80.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Old Lyme CT
 41.31°N 72.36°W (Elev. 30 ft)
Last Update:
2:36 pm EDT May 12, 2026
Forecast Valid:
1am EDT May 13, 2026-6pm EDT May 19, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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