I'm here in Little Cayman now.
I did 3 boat dives today with LCBR Reef Divers. 15 divers on our boat wore wetsuits. 1 more just had a shorty. 1 had swim trunks and a t-shirt. 2, including me wore lycra skins. The DM wore a wetsuit shirt thingy, and swim trunks. It was very windy today with high seas. (Bonine is my friend!) Water temp as recorded by my computer today= 82, 83, and 83. (At home, I swim in my swimsuit for 45min to and hour in a pool heated to 83F. It is a nice temperature, and loads of other Floridians are enjoying swimming there too.) I was comfortable in the water today. I only felt a tiny bit cold toward the end of the first dive. The surface interval was chilly after the first dive because of the wind. A towel and a sit up on top of the boat in the sun, and I was happy. Air temp on the boat was 80-81F. This is not anything worth wearing a wetsuit for me. I don't like the extra weights and prefer to dive in my lycra skin. I plan to continue like this for the week. However, I know I can rent a wetsuit if I want to ($10 p/d).
Next time I will pack 3 swimsuits, no socks or sneakers just sandels and flip flops, a smallish plastic pouch to keep a few things dry and together (gallon size baggie would also work for that), and a (not too big) reusable water bottle would be nice to have. We are in swim suits most of the day. No need for long pants or fancy things here.