Measurements:
°C
°F
Groton
64°F
SE 2 mph
Feels like: 64°F
Precip: 62%
World Resorts USA Groton Weather

Groton Sea Water Temperature

Current Sea Water Temperature:
+50.6°F
Maximum Sea Water Temperature in May: 59.8°F
Minimum Sea Water Temperature in May: 45.8°F
Average water temperature in May: 52.1°F

Sea Water Temperature for the Last 10 Days:

May 14 50.6°F May 09 50.4°F
May 13 49.8°F May 08 49.8°F
May 12 49.4°F May 07 49.2°F
May 11 49.8°F May 06 48.4°F
May 10 50.2°F May 05 46.4°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
December 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 34.6 °F
February 36.0 °F
December 39.9 °F
The most rainy months:
November 3 days
July 3 days
December 3 days
The most windy months:
January 10 mph
December 10 mph
March 10 mph

Groton on the Weather Map

USA Resorts:
NAME
Boston +56
Chicago +56
Hawaii +78
Honolulu +78
Houston +98
Las Vegas +102
Los Angeles +76
Maui +72
Miami +90
Miami Beach +92
New York +70
San Diego +72
San Francisco +72
Sarasota +96
Tampa +96
24 Hours Weather Forecast
Groton
Local time: 14:00
14 may, thursday
1500 64°F
SE
2 mph
1800 62°F
NE
1 mph
2100 56°F
NE
4 mph
15 may, friday
0000 52°F
SW
1 mph
0300 50°F
S
3 mph
0600 50°F
S
5 mph
0900 54°F
S
6 mph
1200 56°F
SE
6 mph