July or August

I still have not been anywhere this summer. I know that I am going to do some adventuring soon, but my plans are not set in stone yet. What I am going to do right now is to decide which time of year is the best for a beach vacation: July or August. The reason I am asking is because I just cannot decide which month seems to be better for this type of vacation. Something tells me that I am going to end up going on a vacation in August. The water in the sea is warmer that it is in July, but the temperature of air remains the same. I hope that I am not wrong about that. Also, there might be fewer people on the beach in August as from my personal experience I can say that most people I know take a vacation in the beginning of the summer as they have been waiting for it for the whole year.