Measurements:
°C
°F
Groton
76°F
E 12 mph
Feels like: 80°F
Precip: 17%
World Resorts USA Groton Weather

Groton Sea Water Temperature

Current Sea Water Temperature:
+73.4°F
Maximum Sea Water Temperature in August: 78.2°F
Minimum Sea Water Temperature in August: 69.2°F
Average water temperature in August: 73.0°F

Sea Water Temperature for the Last 10 Days:

August 25 73.4°F August 20 73.6°F
August 24 73.2°F August 19 73.2°F
August 23 73.0°F August 18 71.6°F
August 22 73.4°F August 17 72.2°F
August 21 74.8°F August 16 73.4°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 73.9°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: 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 83.8 °F
August 81.4 °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 +80
Chicago +78
Hawaii +84
Houston +106
Las Vegas +116
Los Angeles +96
Maui +70
Miami +90
Myrtle Beach +84
New York +86
San Diego +96
San Francisco +74
Santa Monica +86
Sarasota +92
Washington +88
24 Hours Weather Forecast
Groton
Local time: 17:52
25 aug, tuesday
1800 76°F
E
12 mph
2100 72°F
SE
9 mph
26 aug, wednesday
0000 68°F
S
7 mph
0300 66°F
SE
11 mph
0600 64°F
SE
10 mph
0900 70°F
SE
5 mph
1200 76°F
E
11 mph
1500 74°F
NE
15 mph