Quite a bit depends on what the apocalypse was...
If it was due to a meteor hitting the center of the Pacific, most of the land of Florida would be there, but the tidal wave that hit after the impact has been theorized at pretty much erasing everything else, including all of the vegetation from coast to coast. We don't have high enough land to stop it at any point as it travels across the state.
If it was due to some kind of nuclear war, I'm pretty sure portions of the state would survive because we don't have any active fault lines in the state, so we wouldn't have to worry about such things as volcanoes or massive land destroying earthquakes.
Oh yeah, and while we have the occasional military base and massive population center, they’re pretty isolated, so you’d still have major parts of the state around.
If it was due to some kind of biological plague, well, those kinds of plagues only destroy animal life or plant life, so the land would still be here.
If it was due to some kind of major flood, we’ll we’re kinda back to the meteor strike, except that you wouldn’t have any land above sea if the seas rose too much! You might have the occasional high rise poking through the flood waters, which could make for some really interesting gaming scenarios. Once again, it depends on how much water is added to the seas.
If you really want to make sure you’ve got Florida still around after the apocalypse, just use which ever scenario you want and modify it so that Florida survives. If your players really want to play in their local area, they should be ok if you take some artist license when writing up the game background.
Personally, I’ve run apocalypse scenarios in Florida, from zombies to aliens and each time, the PCs have been able to play in our local area and we’ve had lots of fun!