Current sea water temperature:
+67.3°F
| Minimum sea water temperature in September: | 74.1°F |
| Maximum sea water temperature in September: | 60.6°F |
| Average sea water temperature in September: | 68.6°F |
| more information | |
14 days
forecast
forecast
| Nantucket |
monthly
weather
weather
| Nantucket |
Sea water temperature for the last 10 days:
| September 14 | 67.3°F | September 9 | 69.4°F |
| September 13 | 69.6°F | September 8 | 70.7°F |
| September 12 | 69.4°F | September 7 | 70.2°F |
| September 11 | 69.3°F | September 6 | 71.1°F |
| September 10 | 69.4°F | September 5 | 72.0°F |
Monthly sea water temperature, °F
When is the warmest sea in Nantucket?
Based on the data about daily sea water temperature for the last three years the warmest sea in Nantucket was noticed in August, July and September.
Monthly Sea Temperatures in Nantucket, °F
Sea water temperature in August, °F
Show year:
2026
2025
2024
The average sea water temperature in August of 2026 was 71.5°F. The highest and lowest sea temperatures during the month were 73.8°F and 67.6°F.
Sea water temperature in July, °F
Show year:
2026
2025
2024
The average sea water temperature in July of 2026 was 69.5°F. The highest and lowest sea temperatures during the month were 71.8°F and 66.7°F.
Sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 67.7°F. The highest and lowest sea temperatures during the month were 69.4°F and 66.4°F.
current
weather
weather
| Nantucket |
weather in
September
September
| Nantucket |
Best time for vacation in Nantucket
Nantucket on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Nantucket
Local time: 16:41
September 14, monday
1800
68°F
S
21 mph
21 mph
2100
66°F
S
16 mph
16 mph
September 15, tuesday
0000
64°F
S
22 mph
22 mph
0300
64°F
SW
19 mph
19 mph
0600
63°F
SW
19 mph
19 mph
0900
63°F
SW
16 mph
16 mph
1200
63°F
SW
13 mph
13 mph
1500
63°F
SW
14 mph
14 mph
