I found that Wednesday was the least busy.
Monday and tuesday from my experience
A tip for next year: 4th of July was very light, no lines for many coasters!
We went on tuesday an it wasnt to bad the lines for rides were about 5to 10 mins depending on the ride
School is out and alot of tourists are up for the summer so I would say its extremely busy all season
I would assume weekdays must be less busy.
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