Crowds thru December

Does anyone have feedback/experience to share on how they find their crowds develop thru December?
Is the attendance from early Dec to near Christmas an exponential climb? ie: handfuls now and chaos near Christmas? Or do you have steady crowds etc. etc?

I know for my own family we aren't hunting for lights yet and will likely do that the Christmas weekend (this year Dec 21/22) or once school is finished.

US-based. And a colder place. Experience elsewhere will differ.
Crowds this past weekend were good, but about a third of peak. The previous weekends were quite small.
Weekdays are much quieter than weekends.
Weather is a huge factor, people come more when it is nice. Nearby local events also play into it, when they are doing the downtown stroll more people show. Also when the snowman is up, people see the back of the head and come around to see what it is, and we don't use it when it's windy.
You can see a bump if the word is spread on popular channels. The thing that would be the worst is if someone ran a news story on an unseasonably pleasant Saturday the week or two before Xmas. Fortunately hasn't happened, would never have the news do that if I can avoid it.
I don't know if it helps, but anywhere people list the show I try to get them to mention that they might get to pick the song on RF if they come on a quiet day, giveaways are early in the season, etc.

Dead quiet right now, still too early for big crowds. Those come in the 2 weeks before Christmas.

I don't get any more than 1 car at a time most often. From other places I visit with the family, it definitely increases as it nears closer to Christmas eve with some of the places that pull big crowds being impossible to get near on the last few nights and the weekend prior.

It can really depend. It certainly picks up significantly in the lead up to christmas. I would assume on the 20th this year.

That being said - some of the bigger displays that go viral can end up busy through word of mouth much earlier - I know Kings Park lights out your way has a crowd of viewers every night.