March, April and May are all good, warm relatively dry months, although you still get the odd afternoon shower! Temps in the 80's and not so humid as later months,
Make sure it is a suitable SPF. We went to Blizzard Beach in April 2011 with my father-in-law who used factor 8 and then wondered why he had burned. Florida is much further south than we sometimes realise.
Oh dont worry i learnt my lesson foolishly there in 1999 was on a school trip.. Needless to say when we went back in 2009 i was very carefull... Lol.. Thank you though.. we have quite a few different ones.. Nothing worse than geeting sun burn & been in pain for ages..
Is it still warm in the evenings in march do you know?