September is a popular month to ask about Surfside Beach Nantucket because conditions can shift week to week along this coast. Expect the water near 18.0°C, with daily variation from wind, tides and recent storms. We refresh the live value from Open-Meteo Marine every hour, so the headline above always reflects the current state of the Atlantic Ocean.
Surfside Beach Nantucket sea temperature in September — averages 18.0°C
The sea at Surfside Beach Nantucket in United States averages 18.0°C during September, based on long-run climatology for the Atlantic Ocean. Use the live reading below for today's actual water and the monthly grid to compare with the rest of the year.
Average sea · September
18.0°C
mild · Good
Live water now
…
Recommended wetsuit
3/2mm fullsuit
At 18.0°C a 3/2mm fullsuit is the standard wetsuit for surfing and watersports.
Monthly comparison
Yes, but expect a fresh dip · Surfside Beach Nantucket
Can you swim at Surfside Beach Nantucket in June? — 15.0°C water15.0°CCan you swim at Surfside Beach Nantucket in July? — 19.0°C water19.0°CCan you swim at Surfside Beach Nantucket in August? — 20.0°C water20.0°CCan you swim at Surfside Beach Nantucket in September? — 18.0°C water18.0°CCan you swim at Surfside Beach Nantucket in October? — 14.0°C water14.0°CCan you swim at Surfside Beach Nantucket in November? — 10.0°C water10.0°C
Frequently asked questions
What is the average sea temperature at Surfside Beach Nantucket in September?
Surfside Beach Nantucket averages 18.0°C in September, based on long-run climatology for the Atlantic Ocean.
Is the sea warm enough to swim at Surfside Beach Nantucket in September?
It is swimmable but fresh; confident swimmers will be fine without a wetsuit.
Do I need a wetsuit at Surfside Beach Nantucket in September?
A 2 mm shorty is comfortable for sessions over 30 minutes.