Six Flags crowds during July?

[Bat Fastard]

I am going to Six Flags over Texas late July this year. We are for sure going on a Tuesday. We've gone only during mid August before, and never July. Should I expect it to be packed? My mom said we might buy Flash Passes if the lines get crowded.
Also my Dad (parents are divorced) said he might take me and my brother to Chicago this year, which means Six Flags Great America. We'd most likely go mid July, on a weekday. What can I expect for crowds?

 

[njn63]

SF Great America on a weekday is either empty or moderately crowded depending on what school or church group is there that day. Generally everyone is in the water park if it is warm or hot (which it probably will be in mid July) so you should be able to ride everything in the park pretty easily.