Coincidentally, my roughest go at sea diving to date was in FL go figure, in the Keys of all places. It might have been me, my wife and I were the only ones.Oh our conditions can get rocking! Depending up which inlet a boat uses, many of the boats will go out in 3-5' or maybe even 4-6' seas (depending upon the period, tide, direction, etc.) if they know the people on the boat can handle it. That is one reason I check first. If the conditions are more than I feel like tackling, I'll cancel because the boat may not.
Now I have a pretty full proof system (knocks on wood) to not get seasick. edit: scopolamine(sp?) and eating something light before does me great.