World Resorts USA Nantucket Weather

Nantucket sea water temperature

Current sea water temperature:
+58.1°F
Minimum sea water temperature in June: 72.0°F
Maximum sea water temperature in June: 55.0°F
Average sea water temperature in June: 61.7°F

Sea water temperature for the last 10 days:

June 5 58.1°F May 30 56.8°F
June 4 59.5°F May 29 57.0°F
June 3 58.3°F May 28 54.3°F
June 1 55.6°F May 27 55.9°F
May 31 56.8°F May 26 54.1°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:
2025
2024
2023

The average sea water temperature in July of 2025 was 68.7°F. The highest and lowest sea temperatures during the month were 72.9°F and 63.9°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.

Best time for vacation in Nantucket

Sunniest months:
June 13 days
October 13 days
September 13 days
Warmest months:
August 70.9 °F
July 70.6 °F
September 67.1 °F
Warmest sea temp:
August 72.0 °F
July 70.1 °F
September 68.5 °F
Coldest months:
February 36.1 °F
January 36.4 °F
March 40.7 °F
Rainiest months:
October 4 days
January 3 days
December 3 days
Windiest months:
January 19.0 mph
March 19.0 mph
December 18.9 mph

Nantucket on a weather map

Nantucket
+64°F
NE 12 mph
Feels like: +64°F
Precip.: 3%
Places in USA:
Name
°F
+77°F
+77°F
+106°F
+75°F
+75°F
+81°F
+72°F
+77°F
+66°F
+75°F
+66°F
+81°F
+84°F
+79°F
+70°F
24 Hours Forecast
Nantucket
Local time: 21:05
June 06, saturday
0000
61°F
NE
14 mph
0300
59°F
NE
14 mph
0600
61°F
NE
13 mph
0900
61°F
NE
14 mph
1200
63°F
NE
16 mph
1500
63°F
NE
19 mph
1800
63°F
NE
24 mph
2100
63°F
NE
25 mph
Units of measurement: °C / °F