You might get conductive heat from nearby tiles, that makes the white tiles warmer.
When I was in Bermuda, (in the Navy) we had hills on the base that were covered
in concrete and painted bright white. Looked like many of the roofs in Bermuda.
Those white roofs and the white mountains on the base were rain catchment systems.
(There are very few fresh water wells on the island).
In the typical home, there is a little manhole in the kitchen floor.
Lift it up and find the 'basement' is a giant water tank
with catfish swimming around..
Anyways, while I was there (4-15-63 to 4-15-65), it got pretty hot in the summer time.
But, inside of most homes wasn't uncomfortable, since the roof was bouncing
the sunlight away, and a concrete floor sitting on tons of cool water tends to keep it nice..
I didn't know anyone that had AC in their home..