Basically, you will not get an HD signal from a station using a basic antenna setup if you are outside of the red coverage area on Radio-Locator. Now, using an outdoor antenna or a good HD car tuner, I have picked up WXTB HD in SW Orange County no problem. Miami/Ft. Lauderdale radio reception is a totally different ball of wax. Reception is very bizarre and difficult in the area...you got the pirates, the tall towers that have a line-of-sight for miles, and the humid weather. So, it wouldn't suprise me if you can't get WRMF HD in Broward. Try getting an outdoor antenna and see if that helps.
Radio-X