We went March 16-23 this year. It was our first time there..I think we lucked out b/c we had temps in the 80s for 4 days..then it dipped back into the 60s and upper 50s. While we still had a good time during the cooler days, we had a great time when it was warmer.
We probably won't go back again in March b/c we want to make sure it's warm enough for the beach/pool. Next time we go will probably be a June trip.