We were just there and I wasn't prepared for THAT heat! Light, loose clothing. Seriously light; seriously loose, and preferrably lots of linen, cotton stuff. Synthetics stick to you!!!! None of my Montreal summer clothes were appropriate for Summer in Negril! Lots of water. Lots of water - I noticed that practically everyone is walking around with a cell phone and a bottle of something! I am sure you can fry eggs on the sand between 10-11 and 2 pm!!!! And don't run! It's wonderful, though! And carry a towel or wash cloth to wipe the sweat off. Seriously!