We are not local, as far as I know, most Utah schools get only get President's day. Sometimes there is a four day weekend involved but I just checked and our district only has the 18th.
We are in the Los Angeles Unified School District and it is only closed for Presidents Day. We homeschool and still plan on not going down to the park on the 12th. Just too much weekday traffic to deal with.
We have the two Mondays off (President's Day and the Monday before). But we are not a big district like LA Unified so ours wouldn't have an affect on crowds.
You will find different districts doing different things. Some will have a whole week off (my sister's district in No. Cal does this). Some will have the two Mondays. Some will have the Friday before President's Day and the Monday of President's Day.
So it is hard to tell what crowds will be like, but you are guaranteed that the weekend of President's Day will be crowded.