Hi Jennifer,
I think the following is the information from the WDW Website that you are seeking:
Q. What are the busiest and least busy times of the year?
A. Although special events and promotions may influence Theme Park attendance levels, the following list highlights historic attendance trends throughout the year:
Lowest Attendance: January (except New Year's Day) until just prior to Presidents' week in February
The week following Labor Day until just prior to Thanksgiving week
The week following Thanksgiving until the week prior to Christmas
Moderate Attendance: After Presidents' week in February through early March
Late April through early June (except Memorial Day weekend)
The first part of Thanksgiving week
Highest Attendance: Presidents' week in February
Mid-March through Late April ("Spring Break")
Memorial Day weekend
Mid-June through Labor Day
Thanksgiving Day and weekend
Christmas week through New Year's Day
During regular attendance periods the Theme Parks tend to be the busiest on the following days:
Magic Kingdom® Park: Monday, Thursday, and Saturday
Epcot®: Tuesday and Friday
Disney's Hollywood Studios™: Sunday and Wednesday
Disney's Animal Kingdom® Theme Park: Monday, Tuesday and Wednesday
I think you can see from the information above that anytime between Mid-March through Late April ("Spring Break") is considered to be the Highest Attendance period at WDW, so although you may have very comfortable weather during this time, you need to be prepared for large crowds. Hope this helps!
Best wishes,
Brigitta