A meaningless phrase that prefaces relevant information. It is basically unnecessary if not redundant, as one is engaged in the very act of “advising” when issuing a warning, imparting knowledge, or giving advice. “Please be advised” is used excessively by people in law enforcement and sometimes by those who became serious about life at a very late age, and now maintain blogs that purport to warn the public about what is largely one-sided, uninteresting crap.
Ryan: Officer Murphy, please be advised that our suspect is driving a Jeep.
Murphy: Ryan, the fact that you’re advising me is understood in the information you have just given to me. Saying “please be advised” is an unnecessary redundancy that pollutes our radio communication.