Measurements:
°C
°F
Groton
60°F
SW 12 mph
Feels like: 60°F
Precip: 5%
World Resorts USA Groton Weather

Groton Sea Water Temperature

Current Sea Water Temperature:
+72.2°F
Maximum Sea Water Temperature in September: 75.6°F
Minimum Sea Water Temperature in September: 65.0°F
Average water temperature in September: 71.0°F

Sea Water Temperature for the Last 10 Days:

September 15 72.2°F September 10 72.8°F
September 14 71.6°F September 09 72.4°F
September 13 70.6°F September 08 71.4°F
September 12 71.8°F September 07 71.4°F
September 11 72.8°F September 06 72.4°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: 2026 2025 2024

The average sea surface temperature in August 2026 for Groton was 73.7°F. The maximum and minimum values were 70.8°F and 78.2°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Groton was 70.2°F. The maximum and minimum values were 67.2°F and 73.2°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Groton was 72.2°F. The maximum and minimum values were 70.6°F and 73.6°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 83.8 °F
August 81.6 °F
June 77.2 °F
Warmest sea temperature:
August 73.0 °F
July 71.1 °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 +62
Chicago +66
Hawaii +80
Las Vegas +80
Los Angeles +72
Maui +66
Miami +88
Myrtle Beach +78
New York +66
Panama City Beach +90
San Diego +70
San Francisco +60
Santa Monica +72
Sarasota +86
Washington +66
24 Hours Weather Forecast
Groton
Local time: 09:41
15 sep, tuesday
1200 66°F
W
8 mph
1500 66°F
NW
8 mph
1800 66°F
NW
7 mph
2100 66°F
NW
9 mph
16 sep, wednesday
0000 66°F
NW
8 mph
0300 64°F
NE
3 mph
0600 64°F
NE
4 mph
0900 66°F
NE
6 mph