Hey! I have been the first of March, May and December. December is definately the lowest crowds. However, the weather is a little unpredictable. Last year, it was wet and somewhat cold. Out of 6 days we had 2 days of nice weather. The weather the first of March was nice, but it was wall to wall at the MK. In May, we thought the crowds were manageable, but last year it was 95 degrees! We went May of 1999 and the crowds were low and the weather was mid-80's. We have also been December 2001 and the crowds were very low and mid-80's. Both times were perfect we thought. Hope this helps!