We use the inexpensive RADIO SHACK WX RECEIVER model 12-260 here which searches for the active WX RADIO station in your area when you first turn it on...

The smart WX RECEIVERS are nice but being on the move like we are it has to be programed just about every place we stop at.
This radio is battery operated but I added an radio shack adapter cable so i could plug into the trailer 12VDC and remove the batteries.
My WX RADIO is on 24/7 when in camping mode.
Roy Ken