At first I wanted to say it may be the headlight switch. But if your radar is giving you those warnings, then I too would put money on either the alternator OR the battery. Don't leave the battery out just because it's top of the line. I use an Optima Yellow Top in my car, and even those can go bad.

Did this start doing this all of a sudden? Or have you had any problems leading up to this one?

Agreed, you should go to any local auto parts store and have them test both the alternator and battery.