Dangerous, Heat Wave Persists in the Eastern U.S.; Severe Weather Expected in the Central Plains and Mid-Atlantic

A prolonged, dangerous heat wave will persist through the Independence Day weekend across the Ohio Valley, Mid-South, and East Coast. Severe thunderstorms are expected to produce damaging wind gusts from the Upper Ohio Valley into the Mid Atlantic, and across the central Great Plains this afternoon and evening. Large hail and heavy rain is also possible across the Great Plains. Read More >

Current conditions at

Groton / New London, Groton / New London Airport (KGON)

Lat: 41.33°NLon: 72.05°WElev: 10ft.

Fair

73°F

23°C

Humidity 94%
Wind Speed W 5 mph
Barometer 29.86 in (1011.1 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 4 Jul 3:56 am EDT
Extended Forecast for

3 Miles N South Lyme CT

Extreme Heat Warning July 4, 04:16am until July 4, 09:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning July 4, 04:16am until July 4, 09:00pm

    NOW until 9:00pm Sat

    Extreme Heat Warning

  • Independence Day

    High: 96 °F

    Sunny then
    Showers
    Likely

  • Tonight

    Tonight: Showers and thunderstorms likely before 2am, then a slight chance of showers between 2am and 5am.  Mostly cloudy, with a low around 68. Calm wind.  Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 68 °F

    Showers
    Likely

  • Sunday

    Sunday: A chance of showers between 8am and 5pm.  Partly sunny, with a high near 86. Calm wind becoming east around 5 mph in the afternoon.  Chance of precipitation is 40%.

    High: 86 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: A slight chance of thunderstorms before 8pm, then a chance of showers and thunderstorms between 8pm and 2am, then showers likely after 2am.  Mostly cloudy, with a low around 63. Calm wind.  Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 63 °F

    Showers
    Likely

  • Monday

    Monday: Showers likely, with thunderstorms also possible after 11am.  Mostly cloudy, with a high near 78. East wind 6 to 9 mph, with gusts as high as 20 mph.  Chance of precipitation is 60%. New rainfall amounts between three quarters and one inch possible.

    High: 78 °F

    Showers
    Likely

  • Monday Night

    Monday Night: Showers likely and possibly a thunderstorm.  Mostly cloudy, with a low around 62. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 62 °F

    Showers
    Likely

  • Tuesday

    Tuesday: A 50 percent chance of showers.  Partly sunny, with a high near 80.

    High: 80 °F

    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 62.

    Low: 62 °F

    Mostly Cloudy

Detailed Forecast

Independence Day
Showers likely and possibly a thunderstorm after 2pm. Increasing clouds, with a high near 96. Heat index values as high as 105. Calm wind becoming west 5 to 8 mph in the morning. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
Tonight
Showers and thunderstorms likely before 2am, then a slight chance of showers between 2am and 5am. Mostly cloudy, with a low around 68. Calm wind. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
Sunday
A chance of showers between 8am and 5pm. Partly sunny, with a high near 86. Calm wind becoming east around 5 mph in the afternoon. Chance of precipitation is 40%.
Sunday Night
A slight chance of thunderstorms before 8pm, then a chance of showers and thunderstorms between 8pm and 2am, then showers likely after 2am. Mostly cloudy, with a low around 63. Calm wind. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
Monday
Showers likely, with thunderstorms also possible after 11am. Mostly cloudy, with a high near 78. East wind 6 to 9 mph, with gusts as high as 20 mph. Chance of precipitation is 60%. New rainfall amounts between three quarters and one inch possible.
Monday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 62. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
Tuesday
A 50 percent chance of showers. Partly sunny, with a high near 80.
Tuesday Night
Mostly cloudy, with a low around 62.
Wednesday
Mostly sunny, with a high near 84.
Wednesday Night
Partly cloudy, with a low around 66.
Thursday
Mostly sunny, with a high near 89.
Thursday Night
A 30 percent chance of showers. Partly cloudy, with a low around 69.
Friday
A 30 percent chance of showers. Partly sunny, with a high near 91.
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ABOUT THIS FORECAST

 
Point Forecast:
3 Miles N South Lyme CT
 41.35°N 72.32°W (Elev. 200 ft)
3:48 am EDT Jul 4, 2026
4am EDT Jul 4, 2026-6pm EDT Jul 10, 2026
 
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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