Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average sea temperature in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
September
Weather in September
Temperature
The shift into September records an average high-temperature of an enjoyable 67.6°F (19.8°C), subtly varied from August's 72.1°F (22.3°C). During the nights of September, Nantucket maintains an almost steady temperature with an average low of 63.9°F (17.7°C).Humidity
In Nantucket, the average relative humidity in September is 80%.Rainfall
In Nantucket, in September, it is raining for 11.7 days, with typically 2.2" (56mm) of accumulated precipitation. Throughout the year, there are 153 rainfall days, and 26.61" (676mm) of precipitation is accumulated.Snowfall
In Nantucket, snow does not fall in April through October.Ocean temperature
In Nantucket, the average seawater temperature in September is 65.1°F (18.4°C).Note: Swimming is not an enjoyable activity for the majority when the water is at 65.1°F (18.4°C). The difficulty of controlling breathing increases as the temperature dips from 69.8°F (21°C) to 59°F (15°C).
Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:07 am and sunset at 7:12 pm. On the last day of September, sunrise is at 6:36 am and sunset at 6:23 pm EDT.
Sunshine
The average sunshine in September is 8.6h.UV index
In Nantucket, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for average individuals.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Undertake protective steps - Preventing sun damage is advised. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
What is the ocean temperature in September?
What is the average length of the day in September?
When are sunrise and sunset in September?
How long on average sun shines in September?
How high is the UV index in September?
Average temperature in September
Nantucket, MA
- Average high temperature in September: 67.6°F
The warmest month (with the highest average high temperature) is August (72.1°F).
The month with the lowest average high temperature is February (39.7°F).
- Average low temperature in September: 63.9°F
The month with the highest average low temperature is August (68.7°F).
The coldest month (with the lowest average low temperature) is February (32.5°F).
Average pressure in September
Nantucket, MA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Nantucket, MA
- Average wind speed in September: 14mph
The windiest month (with the highest average wind speed) is January (18.5mph).
The calmest month (with the lowest average wind speed) is August (11.8mph).
Average humidity in September
Nantucket, MA
- Average humidity in September: 80%
The month with the highest relative humidity is July (86%).
The months with the lowest relative humidity are January, November and December (75%).
Average rainfall in September
Nantucket, MA
- Average rainfall in September: 2.2"
The wettest month (with the highest rainfall) is October (3.27").
The driest month (with the least rainfall) is November (1.77").
Average rainfall days in September
Nantucket, MA
- Average rainfall days in September: 11.7 days
The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is February (9.2 days).
Average snowfall in September
Nantucket, MA
- Average snowfall in September: 0"
The month with the highest snowfall is January (1.06").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Nantucket, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
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: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 8h and 4min
The months with the most sunshine are July and August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in September
Nantucket, MA
- Average sunshine days in September: 15.7 days
The month with the most sunshine days is August (16.5 days).
The month with the least sunshine days is January (11.3 days).
Average UV index in September
Nantucket, MA
- Average UV index in September: 5
The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January, February, March and December (UV index 2).
Average cloud cover in September
Nantucket, MA
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 54).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Nantucket, MA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).