We returned from 2 weeks last Saturday. On Friday it was up to 39 mid afternoon with no breeze at all and did feel a bit uncomfortable, that said, it was about the same the day before but quite windy so it was lovely. All the years I've been to
Icmeler it's more often than not been pretty breezy May/June so you should be fine. It was warm on the beach last week as the wind was coming from the mountains (I thought it odd at the time and have been wondering if there is any connection with the earthquakes?) but usually it's cooler when it comes off the sea.
If it is too hot, the red lion have already got the water mists on, so you could go hide in there!