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.

Overcast

38°F

3°C

Humidity 93%
Wind Speed N 7 mph
Barometer 29.79 in (1008.6 mb)
Dewpoint 36°F (2°C)
Visibility 7.00 mi
Wind Chill33°F (1°C)
Last update 18 Feb 6:56 pm EST
Extended Forecast for

South Lyme CT

  • Tonight

    Tonight: Rain likely, possibly mixing with snow after 10pm, then gradually ending. Areas of fog before 1am. Otherwise, cloudy, with a low around 29. Calm wind. Chance of precipitation is 70%. Little or no snow accumulation expected.

    Low: 29 °F

    Rain/Snow
    Likely and
    Areas Fog

  • Thursday

    Thursday: Partly sunny, with a high near 40. Calm wind becoming east around 5 mph.

    High: 40 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: A chance of snow between 1am and 4am, then a chance of freezing rain after 4am. Mostly cloudy, with a low around 29. Calm wind. Chance of precipitation is 40%.

    Low: 29 °F

    Mostly Cloudy
    then Chance
    Wintry Mix

  • Friday

    Friday: Rain likely, possibly mixed with freezing rain before 7am, then rain. High near 39. Light east wind increasing to 5 to 9 mph in the morning. Chance of precipitation is 90%. Little or no ice accumulation expected.

    High: 39 °F

    Rain/Freezing
    Rain Likely
    then Rain

  • Friday Night

    Friday Night: Rain and snow likely, mainly before 1am. Cloudy, with a low around 31. Northeast wind around 5 mph becoming calm in the evening. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.

    Low: 31 °F

    Rain/Snow
    Likely

  • Saturday

    Saturday: A chance of rain and snow. Partly sunny, with a high near 40. Chance of precipitation is 40%.

    High: 40 °F

    Chance
    Rain/Snow

  • Saturday Night

    Saturday Night: A chance of rain and snow before 1am. Mostly cloudy, with a low around 26. Chance of precipitation is 30%.

    Low: 26 °F

    Chance
    Rain/Snow

  • Sunday

    Sunday: A 30 percent chance of snow after 1pm. Mostly cloudy, with a high near 36.

    High: 36 °F

    Mostly Cloudy
    then Chance
    Snow

  • Sunday Night

    Sunday Night: A 50 percent chance of snow. Mostly cloudy, with a low around 26.

    Low: 26 °F

    Chance Snow

Detailed Forecast

Tonight
Rain likely, possibly mixing with snow after 10pm, then gradually ending. Areas of fog before 1am. Otherwise, cloudy, with a low around 29. Calm wind. Chance of precipitation is 70%. Little or no snow accumulation expected.
Thursday
Partly sunny, with a high near 40. Calm wind becoming east around 5 mph.
Thursday Night
A chance of snow between 1am and 4am, then a chance of freezing rain after 4am. Mostly cloudy, with a low around 29. Calm wind. Chance of precipitation is 40%.
Friday
Rain likely, possibly mixed with freezing rain before 7am, then rain. High near 39. Light east wind increasing to 5 to 9 mph in the morning. Chance of precipitation is 90%. Little or no ice accumulation expected.
Friday Night
Rain and snow likely, mainly before 1am. Cloudy, with a low around 31. Northeast wind around 5 mph becoming calm in the evening. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.
Saturday
A chance of rain and snow. Partly sunny, with a high near 40. Chance of precipitation is 40%.
Saturday Night
A chance of rain and snow before 1am. Mostly cloudy, with a low around 26. Chance of precipitation is 30%.
Sunday
A 30 percent chance of snow after 1pm. Mostly cloudy, with a high near 36.
Sunday Night
A 50 percent chance of snow. Mostly cloudy, with a low around 26.
Monday
A 40 percent chance of snow before 1pm. Mostly cloudy, with a high near 36.
Monday Night
Partly cloudy, with a low around 22.
Tuesday
Sunny, with a high near 36.
Tuesday Night
Mostly clear, with a low around 18.
Wednesday
Mostly sunny, with a high near 40.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
South Lyme CT
 41.32°N 72.29°W (Elev. 98 ft)
Last Update:
12:48 pm EST Feb 18, 2026
Forecast Valid:
7pm EST Feb 18, 2026-6pm EST Feb 25, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation