Measurements:
°C
°F
CURRENT WEATHER
10:28
Groton
60°F
SW 11 mph
Feels like: 60°F
Precip: 6%
World Resorts USA Groton Weather

7 Day Weather Forecast

09.15
tue
DAY
66°F
W 6 mph
precip
3%
NIGHT
66°F
N 9 mph
precip
6%
09.16
wed
DAY
70°F
NE 9 mph
precip
5%
NIGHT
70°F
E 9 mph
precip
11%
09.17
thu
DAY
74°F
N 9 mph
precip
11%
NIGHT
72°F
NE 11 mph
precip
12%
09.18
fri
DAY
74°F
SE 9 mph
precip
18%
NIGHT
62°F
SW 15 mph
precip
13%
09.19
sat
DAY
64°F
W 11 mph
precip
7%
NIGHT
66°F
N 13 mph
precip
15%
09.20
sun
DAY
70°F
NE 22 mph
precip
86%
NIGHT
60°F
S 16 mph
precip
26%
09.21
mon
DAY
66°F
W 11 mph
precip
8%
NIGHT
64°F
W 12 mph
precip
18%

Groton Sea Water Temperature in September, °F

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Groton was 21.1°F. The maximum and minimum values were 20.3°F and 21.8°F respectively.

Groton on the Weather Map

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
more details