Nantucket
Massachusetts, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Nantucket, MA

Beautiful homes built on the water overlooking the boats on the water below, in Nantucket, Massachusetts, with stunning pink, sun rays
Beautiful homes built on the water overlooking the boats on the water below, in Nantucket, Massachusetts, with stunning pink, sun rays
September, the first month of the autumn, in Nantucket, is also an agreeable month, with average temperature varying between 69.4°F (20.8°C) and 56.1°F (13.4°C).

Temperature

In Nantucket, the average high-temperature in September is relatively the same as in August - an agreeable 69.4°F (20.8°C). In September, in Nantucket, the average low-temperature is 56.1°F (13.4°C).

Rainfall

In Nantucket, during September, the rain falls for 8 days and regularly aggregates up to 4" (102.6mm) of precipitation. Throughout the year, there are 120 rainfall days, and 44.4" (1128.3mm) of precipitation is accumulated.

Snowfall

Throughout the year, in Nantucket, 29.3" (744.2mm) of snow is accumulated.

Ocean temperature

In Nantucket, Massachusetts, the average water temperature is 65.1°F (18.4°C). For most, swimming in 65.1°F (18.4°C) is not an enjoyable activity. Furthermore, controlling your breathing becomes progressively more difficult as the water temperature decreases from 69.8°F (21°C) to 59°F (15°C).

Daylight

In Nantucket, the average length of the day is 12.5h.

Sunshine

In Nantucket, the average sunshine in September is 8h.

UV index

In Nantucket, the average daily maximum UV index is 6. A UV Index of 6 to 7 symbolizes a high health hazard from unprotected exposure to the Sun's UV rays for the ordinary person.
In September, the average maximum UV index of 6 translate into the following recommendations:
Take precautions against overexposure. Fair-skinned people may get burned in less than 20 minutes. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.

What is the temperature in September in Nantucket?

In September, in Nantucket, the average high-temperature is 69.4°F (20.8°C), and the average low-temperature is 56.1°F (13.4°C).

How many days does it rain in September in Nantucket?

In Nantucket, Massachusetts, during September, the rain falls for 8 days and regularly aggregates up to 4" (102.6mm) of precipitation.

What is the ocean temperature in September in Nantucket?

In Nantucket, Massachusetts, in September, the average water temperature is 65.1°F (18.4°C). For most, swimming in 65.1°F (18.4°C) is not an enjoyable activity. Furthermore, controlling your breathing becomes progressively more difficult as the water temperature decreases from 69.8°F (21°C) to 59°F (15°C).

How many hours of daylight does Nantucket have in September?

In September, the average length of the day in Nantucket, Massachusetts, is 12.5h.

How long on average sun shines in September in Nantucket?

In September, the average sunshine in Nantucket is 8h.

How high is the UV index in September in Nantucket?

In September, the average daily maximum UV index in Nantucket is 6. A UV Index reading of 6 to 7 represents a high health threat from unprotected exposure to the UV radiation.
Average temperature in September - Nantucket, MA
  • Average high temperature in September: 69.5°F

The warmest month (with the highest average high temperature) is July (75.1°F).
The month with the lowest average high temperature is January (38.1°F).

  • Average low temperature in September: 56.2°F

The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is January (25.1°F).

Average rainfall in September - Nantucket, MA
  • Average rainfall in September: 4"

The wettest month (with the highest rainfall) is November (4.4").
The driest month (with the lowest rainfall) is February (2.7").

Average rainfall days in September - Nantucket, MA
  • Average rainfall days in September: 8 days

The month with the highest number of rainy days is December (13 days).
The month with the lowest number of rainy days is July (7 days).

Average snowfall in September - Nantucket, MA
  • Average snowfall in September: 0"

The month with the highest snowfall is February (8.5").
Months with the lowest snowfall are May, June, July, August, September and October (0").

Average sea temperature in September - Nantucket, MA
  • Average sea temperature in September: 65.1°F

The best month for swimming (with the highest average sea temperature) is August (67.6°F).
The coldest month (with the lowest average sea temperature) is February (37.9°F).

Average daylight in September / Average sunshine in September - Nantucket, MA
  • Average daylight in September: 12.5h

The month with the longest days is June (Average daylight: 15.1h).
The month with shortest days is December (Average daylight: 9.3h).

  • Average sunshine in September: 8h

The month with most sunshine is June (Average sunshine: 9h).
Months with least sunshine are January, November and December (Average sunshine: 5).

Average UV index in September - Nantucket, MA
  • Average UV index in September: 6

Months with the highest UV index are June, July and August (UV index 8).
The month with the lowest UV index is December (UV index 1).