If your HDTV has a built-in tuner (HDTVs manufactured in the last couple of years are required to have them by law), you have a proper antenna capable of receiving the HDTV broadcast signals (usually almost any UHF antenna will do), and are in a location where you can actually get the signal reliably, it shouldn't be a problem. You don't even have to mount an antenna outside if you use something like the Silver Sensor antenna (Google this) which you just place on your TV or A/V cabinet and point it to the broadcast source.
I would check with your neighbors or other people in your neighborhood to see if anyone is getting HDTV OTA. Find out what kind of antenna they're using. Unless there are some very tall buildings between you and the broadcast source and you're not more than 10-20 miles away, it should be a piece of cake. I can't image that in Florida geography plays any significant role in determining ability to receive a signal.
Go to
AVS Forums and look for the HDTV forums. There is one for "Local HDTV Info and Reception" and "HDTV Reception Hardware". You should be able to find all the info you need.