Re: Cold?
Seconded.
I have some recollections from an old trip to Finland in early July. I remember swimming and windsurfing off Espo in Helsinki bay which had the water at 24C and the air at 30C with 22 hours of non-stop (albeit a big hazy) sunshine. The only unpleasant part was the ridiculous humidity.
At the same time, the supposedly subtropical Black Sea* was still at freezing cold 16-18C (I was there just the week before going to Helsinki).
*In those days it was nowhere near as polluted and overfished as now so there was none of the positive feedback of algae->better absorb heat from sun->more algae blooms of today.