im wondering when the best time of year is to visit southern thai beaches...when the sands are the whitest and water the clearest. from what i understand after the rainy season the beaches can look a little less appealing?
I reckon March-early April. Still dry season but also shoulder meaning fewer crowds, easier walk-in vacancies. And yep, the water has had time to clear from any wet-season turbidity.
Having said that, I don't mind late November-early Dec. Dry season has usually kicked in everywhere except Samui and neighbours, is still shoulder and most places have cleaned the beach of wet season junk and the usual fishing boats cast-offs. Water usually fairly clear with the exception of islands close to shore or off big rivers (eg latter - Ko Phayam and little Ko Chang Andaman side).