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

47°F

8°C

Humidity 97%
Wind Speed N 5 mph
Barometer 30.43 in (1030.4 mb)
Dewpoint 46°F (8°C)
Visibility 10.00 mi
Wind Chill45°F (7°C)
Last update 11 Oct 4:56 am EDT
Extended Forecast for

Old Lyme CT

  • Today

    Today: Rain, mainly after 2pm. High near 63. Light east wind becoming southeast 5 to 9 mph in the morning. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    High: 63 °F

    Slight Chance
    Rain then
    Rain

  • Tonight

    Tonight: Rain before 11pm, then rain and possibly a thunderstorm between 11pm and 2am, then a chance of rain and thunderstorms after 2am. Low around 52. East wind 7 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 52 °F

    Rain

  • Columbus Day

    Columbus Day: Mostly cloudy through mid morning, then gradual clearing, with a high near 71. North wind 7 to 9 mph, with gusts as high as 20 mph.

    High: 71 °F

    Becoming
    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 51. Calm wind.

    Low: 51 °F

    Mostly Clear

  • Tuesday

    Tuesday: Partly sunny, with a high near 67. Light and variable wind becoming southeast 5 to 8 mph in the morning.

    High: 67 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers. Mostly cloudy, with a low around 58.

    Low: 58 °F

    Chance
    Showers

  • Wednesday

    Wednesday: Mostly sunny, with a high near 73.

    High: 73 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 46.

    Low: 46 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 64.

    High: 64 °F

    Sunny

Detailed Forecast

Today
Rain, mainly after 2pm. High near 63. Light east wind becoming southeast 5 to 9 mph in the morning. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Tonight
Rain before 11pm, then rain and possibly a thunderstorm between 11pm and 2am, then a chance of rain and thunderstorms after 2am. Low around 52. East wind 7 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Columbus Day
Mostly cloudy through mid morning, then gradual clearing, with a high near 71. North wind 7 to 9 mph, with gusts as high as 20 mph.
Monday Night
Mostly clear, with a low around 51. Calm wind.
Tuesday
Partly sunny, with a high near 67. Light and variable wind becoming southeast 5 to 8 mph in the morning.
Tuesday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 58.
Wednesday
Mostly sunny, with a high near 73.
Wednesday Night
Mostly clear, with a low around 46.
Thursday
Sunny, with a high near 64.
Thursday Night
Partly cloudy, with a low around 44.
Friday
A 50 percent chance of showers. Mostly cloudy, with a high near 65.
Friday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 46.
Saturday
A 30 percent chance of showers. Partly sunny, with a high near 60.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Old Lyme CT
 41.33°N 72.35°W (Elev. 3 ft)
Last Update:
5:35 am EDT Oct 11, 2026
Forecast Valid:
5am EDT Oct 11, 2026-6pm EDT Oct 17, 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