19.09
sat
sat
Day
63°F
W 7 mph
Precip.
12%
12%
Night
61°F
NW 11 mph
Precip.
15%
15%
20.09
sun
sun
Day
64°F
NW 11 mph
Precip.
17%
17%
Night
66°F
NW 14 mph
Precip.
86%
86%
21.09
mon
mon
Day
59°F
SW 21 mph
Precip.
37%
37%
Night
59°F
SW 17 mph
Precip.
21%
21%
22.09
tue
tue
Day
57°F
SW 22 mph
Precip.
25%
25%
Night
55°F
SW 22 mph
Precip.
72%
72%
23.09
wed
wed
Day
63°F
W 28 mph
Precip.
20%
20%
Night
61°F
SW 24 mph
Precip.
20%
20%
24.09
thu
thu
Day
59°F
SW 25 mph
Precip.
65%
65%
Night
57°F
SW 22 mph
Precip.
41%
41%
25.09
fri
fri
Day
61°F
SW 16 mph
Precip.
6%
6%
Night
59°F
SW 10 mph
Precip.
13%
13%
Sea water temperature in September, °F
Show year:
2026
2025
2024
The average sea water temperature in September of 2026 was 69.9°F. The highest and lowest sea temperatures during the month were 71.2°F and 68.0°F.
Sea water temperature in October, °F
Show year:
2025
2024
2023
The average sea water temperature in October of 2025 was 65.0°F. The highest and lowest sea temperatures during the month were 69.4°F and 60.4°F.
Air temperature in Groton, °F
Precipitation total in Groton, in.
* Charts above show average data for the last 3 years.
Best time for vacation in Groton
Groton on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Groton
Local time: 06:09
September 19, saturday
0900
57°F
SW
12 mph
12 mph
1200
63°F
W
7 mph
7 mph
1500
63°F
NW
10 mph
10 mph
1800
63°F
NW
9 mph
9 mph
2100
63°F
NW
11 mph
11 mph
September 20, sunday
0000
61°F
NW
11 mph
11 mph
0300
61°F
NW
9 mph
9 mph
0600
61°F
NW
10 mph
10 mph
