Can you swim at Island Beach State Park in September? — 21.0°C water
Yes — comfortable for most swimmers
Average sea · September
21.0°C
Live water now
…
Recommended wetsuit
Shorty 2mm
warm
Yes. With a 21.0°C average in September, most swimmers find Island Beach State Park comfortable after the first 10–20 seconds of acclimatisation.
Monthly averages set expectations, but the specific beach today depends on wind, swell and recent weather. Check the live value at the top of this page or open the Island Beach State Park live page for full conditions.
Best months to swim
July · August
Frequently asked questions
What is the average sea temperature at Island Beach State Park in September?
Island Beach State Park averages 21.0°C in September, based on long-run climatology for the Atlantic Ocean.
Is the sea warm enough to swim at Island Beach State Park in September?
Yes, most swimmers find 21.0°C comfortable for unrestricted swimming.
Do I need a wetsuit at Island Beach State Park in September?
Most swimmers don't need a wetsuit; a rash vest helps for longer sessions.
