Tempe, ARIZONA!!!!!! 65 to 75 degrees and sunny. No wind. No motorboats except coaching launches. Inexpensive, quality hotels. If you haven't been, you should come check it out!
My favorite training venue would have to be at Sandy Run Regional Rowing Facility. Masters Nationals were held there a while back. Got a nice sized boathouses, a large erg room, and miles of wide and calm water to row on.
Except its closed during the winter.
Our team just got back from Cocoa Beach, Fl. It has miles of calm water to row on and any boat traffic there is has to limit its wake because of manatees in the area.