September is a popular month to ask about Montauk Beach because conditions can shift week to week along this coast. Expect the water near 20.0°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.
Montauk Beach sea temperature in September — averages 20.0°C
The sea at Montauk Beach in United States averages 20.0°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
20.0°C
warm · Good
Live water now
…
Recommended wetsuit
Shorty 2mm
At 20.0°C a 2mm shorty keeps surfers warm; lap swimmers can usually skip the neoprene.
Monthly comparison
Yes — comfortable for most swimmers · Montauk Beach
Can you swim at Montauk Beach in June? — 18.0°C water18.0°CCan you swim at Montauk Beach in July? — 22.0°C water22.0°CCan you swim at Montauk Beach in August? — 23.0°C water23.0°CCan you swim at Montauk Beach in September? — 20.0°C water20.0°CCan you swim at Montauk Beach in October? — 16.0°C water16.0°CCan you swim at Montauk Beach in November? — 11.0°C water11.0°C
Frequently asked questions
What is the average sea temperature at Montauk Beach in September?
Montauk Beach averages 20.0°C in September, based on long-run climatology for the Atlantic Ocean.
Is the sea warm enough to swim at Montauk Beach in September?
Yes, most swimmers find 20.0°C comfortable for unrestricted swimming.
Do I need a wetsuit at Montauk Beach in September?
Most swimmers don't need a wetsuit; a rash vest helps for longer sessions.