Average daily temperature during the week of 8 September 2025 - 14 September 2025 was 20 °C (68 °F), average minimal (night) temperature was 12 °C (54 °F). The current temperatures are roughly same as the long-term average for Nantucket, with the daily and nighttime temperatures being 22 °C (72 °F) and 14 °C (57 °F), respectively. The average temperatures during different times of day (local time) were following: 7am 16 °C (61 °F), 10am 19 °C (66 °F), 1pm 20 °C (68 °F), 4pm 20 °C (68 °F), 7pm 17 °C (63 °F), 10pm 15 °C (59 °F).

During this week: 5 days without rain, 1 day with light rain and 1 day with moderate rain were observed. During the whole week, total of 20 mm (0.79 in) of precipitation was observed, which is roughly same as the long term average for Nantucket, which is 21 mm (0.83 in). On average, the cloud coverage during daylight hours (from dawn to dusk) was 23 %. There was a meteorological observation of mist.

Average speed of wind was 4.6 m/s. The air pressure was 1016 hpa - 1027 hpa. The average air humidity was 78 % in Nantucket.

On average, there were 10.5 hours clear skies, 0.5 hours partially overcast skies, 2 hours overcast skies and 1 hour rainy weather during the daytime (from dawn to dusk). The sunrise on average occurred at 06:17, and the sunset occurred at 18:57.

Weather overview

Nantucket (United States of America) is a place with a mild climate. The day temperatures range from 4 °C (39 °F) in January to 25 °C (77 °F) in July. Temperatures during the night go from -3 °C (26 °F) in January to 17 °C (63 °F) in July. The least rainy month in Nantucket is September with its 8 days of rain, the rainiest month is December, when it rains 12 days. Sea temperatures are in the following range: 4 °C (38 °F) in February to 19 °C (67 °F) in August.

January weather

The sea temperature continues to descent, with its value of 5 °C (41 °F) in Nantucket, while the minimum of the day temperature can be noticed, the value of this measure is 4 °C (39 °F). The beginning of the descent of the number of rainy days could be noticed, with its value being 11 days, and the beginning of the descent of the rainfall amount could be noticed as well. The minimum of the night temperature can be noticed, its value is -3 °C (26 °F). The maximum of the wind speed can be noticed in January.

February weather

The beginning of the rise of the day temperature could be noticed, with its value being 5 °C (40 °F) in Nantucket, while the minimum of the sea temperature is observable in February. The beginning of the rise of the night temperature could be noticed, its value is -3 °C (27 °F). The number of sun hours (without clouds) rises similarly to the previous month, with its value of 6 hours. The humidity reaches its minimum, with its value of 66 %.

March weather

The beginning of the rise of the rainfall amount could be noticed, with its value of 98 mm (3.85 in) in Nantucket. The rise of the day temperature can be observed, the value of this measure is 8 °C (46 °F), and the night temperature continues to rise too, its value is 0 °C (32 °F). The number of sun hours (without clouds) continues to rise, with its value of 7 hours.

April weather

The sea temperature starts to rise, its value is 6 °C (43 °F) in Nantucket, while the rise of the day temperature can be observed, its value is 12 °C (53 °F). The night temperature continues to rise, the value of this measure is 4 °C (39 °F). The number of sun hours (without clouds) continues to rise, the value of this measure is 7 hours.

May weather

The sea temperature continues to rise, with its value of 10 °C (49 °F) in Nantucket, and the day temperature rises similarly to the previous month too, with its value of 16 °C (62 °F). The night temperature rises similarly to the previous month. The rise of the number of sun hours (without clouds) can be observed, with its value being 8 hours.

June weather

The rise of the day temperature can be observed, with its value being 22 °C (71 °F) in Nantucket, and the sea temperature continues to rise too, with its value being 14 °C (57 °F). The night temperature rises similarly to the previous month, with its value of 14 °C (57 °F). The maximum of the number of sun hours (without clouds) is observable, with its value of 9 hours. The rainfall amount starts to descent, the value of this measure is 77 mm (3.03 in). The day length is on its maximum, its value is 15 hours.

July weather

The maximum of the day temperature can be noticed, with its value being 25 °C (77 °F) in Nantucket, while the sea temperature continues to rise, its value is 18 °C (64 °F). The number of rainy days descent's start could be observed, while the rainfall amount is on its minimum in July. The tourist season slowly starts. The maximum of the night temperature can be noticed, its value is 17 °C (63 °F).

August weather

There is pending tourist season this month in Nantucket. The rainfall amount starts to rise, its value is 78 mm (3.09 in). The number of sun hours (without clouds) continues to descent, with its value being 8 hours. The maximum of the humidity can be noticed in this month. The maximum of the sea temperature can be noticed, with its value being 19 °C (67 °F).

September weather

The day temperature starts to descent, with its value of 22 °C (71 °F) in Nantucket, and the sea temperature starts to descent too in this month. The minimum of the number of rainy days is observable, with its value being 8 days, while the rainfall amount rises similarly to the previous month, with its value of 89 mm (3.51 in). The night temperature starts to descent, with its value being 14 °C (58 °F). The number of sun hours (without clouds) continues to descent, with its value of 7 hours.

October weather

The descent of the day temperature can be observed, the value of this measure is 17 °C (62 °F) in Nantucket, and the descent of the sea temperature can be observed as well, the value of this measure is 15 °C (58 °F). The night temperature continues to descent, with its value of 9 °C (48 °F). The number of rainy days starts to rise in this month. The number of sun hours (without clouds) descents similarly to the previous month, the value of this measure is 7 hours.

November weather

The descent of the day temperature can be observed, its value is 12 °C (54 °F) in Nantucket, and the sea temperature continues to descent too, with its value of 11 °C (51 °F). The number of rainy days rises similarly to the previous month, with its value of 10 days, while the rainfall amount rise's start could be observed in this month. The number of sun hours (without clouds) continues to descent, with its value being 5 hours. The descent of the night temperature can be observed, with its value being 4 °C (40 °F).

December weather

The sea temperature descents similarly to the previous month, the value of this measure is 7 °C (45 °F) in Nantucket, and the descent of the day temperature can be observed too, with its value of 7 °C (45 °F). The number of rainy days is on its maximum, and the maximum of the rainfall amount is observable as well, the value of this measure is 111 mm (4.38 in). The descent of the night temperature can be observed, the value of this measure is 0 °C (31 °F). The minimum of the number of sun hours (without clouds) is observable in December.

Is June a good month to visit Nantucket?

Nantucket can be visited in June - the weather will be moderate. The temperature of 14 °C (57 °F) at night may make it better to dine inside or to put on more clothes for a dinner outside.

What temperature can I expect during the day in July in Nantucket?

In Nantucket in July, the average daily temperatures will be 25 °C (77 °F). A comfortable temperature for most people, where it is neither too cold nor too hot, and a large number of activities can be carried out comfortably, including sunbathing by the water. Lighter clothing will be suitable - shorts, skirts, t-shirts, jackets; a light sweater and long trousers may also be useful.

Is August part of the wet season in Nantucket?

No, there is no wet season in Nantucket in August - you can expect 9 days of rain during the month.

What is the sea temperature in September in Nantucket?

In Nantucket in September expect the sea to be warm at 18 °C (64 °F). At this sea temperature, swimming probably won't be the best experience. You probably won't like to stay in water for a long time. On the other hand, there are a minority of people who seek these conditions.

What is the average number of rainy days in Nantucket in October?

There are 9 days, which are rainy in Nantucket in October, that is, days with precipitation more than 2 mm (0.08 in). Converted to days of the week, this means that it will occur on an average of 2.1 days of the week, or in general - 30 % days.