I like going in November

for me the weather is just right and the parks although busy seem not to have the volume of numbers as in the school holiday times.

It does get darker a bit earlier but that for me is no problem. You may need a jumper in the evening times if you feel the cold. During the day I was out and about in a tee shirt and shorts

You also get the Sales around Thanksgiving time - now that is "an experience" [msneek]

If you go into the December week you get the Christmas feel in the parks too