How cold is the ocean temperature in Santorini/Mykonos/Paros? July, Aug, Sep?

I was in Santorini last July/August and I don't remember the water being too cold. The island itself wasn't too hot because of the ocean breeze but I don't remember freezing in the water, i just remember it being refreshing. As someone else said, the hot springs are great! I was briefly in Paros for one night as well and it was the same; I never noticed the water being cold and we were swimming at night there.

The Aegean Sea isnot an ocean. Having said that, the Turkish side of the sea has become quite warm. It depends on the currents in the sea, but if you like your sea cool, try swimming at the start of June.

I was in Santorini in July and the water was pretty cold. Very hot weather, but since it's an island it has a nice breeze. At the end of the island there is a huge rock which people jump off, its a really high jump and its scary, but very fun. But it's pretty cold, although if you take the volcano boat tour, you go swimming in the hot springs and that water feels so nice. Enjoy yourself, Santorini is my favorite place I've ever been to in my life!!