Measurements:
°C
°F
Groton
10°F
S 6 mph
Feels like: 2°F
Precip: 0%
World Resorts USA Groton Weather

Groton Sea Water Temperature

Current Sea Water Temperature:
+49.6°F
Maximum Sea Water Temperature in December: 53.8°F
Minimum Sea Water Temperature in December: 42.8°F
Average water temperature in December: 48.8°F

Sea Water Temperature for the Last 10 Days:

December 05 49.6°F November 30 51.0°F
December 04 50.2°F November 29 51.4°F
December 03 50.2°F November 28 52.0°F
December 02 50.4°F November 27 51.6°F
December 01 50.8°F November 26 51.6°F

When is the Warmest Sea for Groton?

According to our data for the last three years for Groton the highest average sea water temperature was in August, July and September.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Groton was 72.6°F. The maximum and minimum values were 70.8°F and 76.8°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Groton was 72.1°F. The maximum and minimum values were 67.4°F and 75.2°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Groton was 70.8°F. The maximum and minimum values were 69.6°F and 73.2°F respectively.

Best Time to Visit Groton
The most sunny months:
November 17 days
October 14 days
September 13 days
The most warm months:
July 83.2 °F
August 81.4 °F
June 76.1 °F
Warmest sea temperature:
August 72.9 °F
July 71.2 °F
September 70.9 °F
The most cold months:
January 35.3 °F
February 36.7 °F
December 40.7 °F
The most rainy months:
November 3 days
July 3 days
January 3 days
The most windy months:
January 10 mph
March 10 mph
November 9 mph

Groton on the Weather Map

USA Resorts:
NAME
Chicago -2
Hawaii +78
Honolulu +78
Houston +44
Las Vegas +38
Los Angeles +50
Maui +70
Miami +68
Miami Beach +80
New York +16
San Diego +52
San Francisco +46
Sarasota +64
Tampa +62
Washington +26
24 Hours Weather Forecast
Groton
Local time: 04:51
05 dec, friday
0600 10°F
S
6 mph
0900 16°F
S
3 mph
1200 24°F
N
6 mph
1500 26°F
NE
7 mph
1800 26°F
N
4 mph
2100 28°F
N
4 mph
06 dec, saturday
0000 30°F
N
2 mph
0300 32°F
N
1 mph