Current sea water temperature:
+69.3°F
| Minimum sea water temperature in July: | 75.6°F |
| Maximum sea water temperature in July: | 63.9°F |
| Average sea water temperature in July: | 70.1°F |
| more information | |
14 days
forecast
forecast
| Nantucket |
monthly
weather
weather
| Nantucket |
Sea water temperature for the last 10 days:
| July 16 | 69.3°F | July 11 | 67.3°F |
| July 15 | 68.9°F | July 10 | 68.0°F |
| July 14 | 68.5°F | July 9 | 69.3°F |
| July 13 | 69.4°F | July 8 | 69.6°F |
| July 12 | 70.0°F | July 7 | 70.5°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:
2025
2024
2023
The average sea water temperature in August of 2025 was 69.7°F. The highest and lowest sea temperatures during the month were 73.2°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 69.2°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
July
July
| Nantucket |
Best time for vacation in Nantucket
Nantucket on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Nantucket
Local time: 08:00
July 16, thursday
0900
75°F
E
11 mph
11 mph
1200
82°F
NE
14 mph
14 mph
1500
81°F
NE
17 mph
17 mph
1800
79°F
NE
22 mph
22 mph
2100
75°F
E
21 mph
21 mph
July 17, friday
0000
75°F
S
20 mph
20 mph
0300
72°F
S
4 mph
4 mph
0600
73°F
SE
12 mph
12 mph
