It has been many years since i've visited in April, however, my sister goes every year, the dates you are talking about happen to be when she goes. She doesn't mind it, however, she is used to it. I do know that last year, DH & I went from May 18 til the 23rd and it was HOT!!! The crowds were not bad at all, but it was so intensely hot, mid-upper 90s, not my idea of optimum park touring weather! I will not be doing a repeat of the May trip!