Hi Tiffany!
Your question is a great one and something we all want to know. It is very difficult to predict the times of year the crowds are the smallest at
Walt Disney World because it depends on so many different factors (special events, weather, etc.) I have noticed, though, that the crowds seem to go along with school holidays. For example,
Christmas and summer vacation times (when school is out) are usually more crowded than the middle of September or February (when school is in session.) As for the weather, that is tough to predict, as well. There have been times we have been at Walt Disney World in June and had cool weather and times we have been there in November and it has been unseasonably warm. Typically, though, late Fall and late Spring have been the seasons we have had the most mild temperatures visiting there.'
I do need to add that, no matter the crowds or the weather, there is always fun to be had and memories to be made. Whatever time of year you decide on, you just can't lose. It's always the most wonderful time of the year at Walt Disney World!
I hope this helps you with your planning. Please let us know if we can do anything else to help you.
Have a magical day!
-Nancy-