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

67°F

19°C

Humidity 57%
Wind Speed S 10 mph
Barometer 30.38 in (1028.5 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Last update 15 Sep 12:56 pm EDT
Extended Forecast for

Old Lyme CT

  • This Afternoon

    This Afternoon: Sunny, with a high near 70. Southeast wind around 6 mph.

    High: 70 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 54. South wind around 5 mph becoming calm in the evening.

    Low: 54 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 74. Calm wind becoming southwest 5 to 7 mph in the morning.

    High: 74 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 62. Calm wind.

    Low: 62 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 78. Calm wind becoming south 5 to 8 mph in the afternoon.

    High: 78 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 65.

    Low: 65 °F

    Mostly Cloudy
    then Chance
    Showers

  • Friday

    Friday: A 30 percent chance of showers before 8am. Mostly sunny, with a high near 79.

    High: 79 °F

    Chance
    Showers then
    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 54.

    Low: 54 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 71.

    High: 71 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 70. Southeast wind around 6 mph.
Tonight
Mostly clear, with a low around 54. South wind around 5 mph becoming calm in the evening.
Wednesday
Mostly sunny, with a high near 74. Calm wind becoming southwest 5 to 7 mph in the morning.
Wednesday Night
Partly cloudy, with a low around 62. Calm wind.
Thursday
Mostly sunny, with a high near 78. Calm wind becoming south 5 to 8 mph in the afternoon.
Thursday Night
A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 65.
Friday
A 30 percent chance of showers before 8am. Mostly sunny, with a high near 79.
Friday Night
Partly cloudy, with a low around 54.
Saturday
Mostly sunny, with a high near 71.
Saturday Night
A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 57.
Sunday
A 50 percent chance of showers. Mostly cloudy, with a high near 76.
Sunday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 59.
Monday
A 40 percent chance of showers. Mostly cloudy, with a high near 72.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Old Lyme CT
 41.31°N 72.33°W (Elev. 43 ft)
Last Update:
2:07 am EDT Sep 15, 2026
Forecast Valid:
1pm EDT Sep 15, 2026-6pm EDT Sep 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