When we went almost two yrs. ago, it was still a little cool. Very cool in the mornings, warmer in the afternoon, and really cool in the evenings. We were able to swim one day while we were there, but the air was still a bit chilly (but we were bound and determined that we were going to swim). It only rained once though, on the very last day. We were there 3/17-3/23, not sure if this is the norm temp. for this time of year.
Also it was very crowded the year we went, I thought that it wouldn't be but apparently alot of colleges and Florida schools were out at this time...