Disney must think that it is going to be a slow time as Disney World closes on 4/23 & 4/24 at 7pm. Which I am disappointed at since there will be no Wishes!!! I am so sorry that I will be missing that!!
The Farmers Almanac says the weather is suppose to be sunny & warm!! I am hoping so!!!
It should be fairly busy bur not overly crowded. The Magic Kingdom is currently scheduled to stay open until 9:00 P.M. or 9:30 P.M. from April 25 - 29. There will be a "Wishes" each night. However, as Sandy297 stated, the MK closes at 7:00 P.M. on April 23 and 24.
If there weather is close to its usual, it'll be warm during the day and nice during the evening. The real humidity hasn't really arrived yet, so hopefully the rain will be almost non-existent. Enjoy!
karylrocks is correct. Those 2 nights are grad nights, so that is the only reason it is closing early. No reflection on crowds. If anything, the other parks, MGM/EPCOT will be busier because of it.