I've wondered and had my own assumptions about why Houston was chosen, but this video succinctly explains the rationale behind why Houston was chosen as NASA's preferred location. Personally, I thought it had something to do with radio communication accessibility at first and the sheer amount of engineering expertise that is here in TX, after thinking things through, I realized that Houston and FL weren't really that far apart so comms weren't the issue. Interesting rationale. Hope you enjoy OB.
For some reason I can't post directly to OB, apologies in advance. Here is the Link.