Whoaaa or Whoaaa na is an exaggerated term of whoa. In Louisiana Whoaaa is a form of greeting or acknowledgment to someone greeting you.
An informal or simple friendly greeting…
Whoaaa, what’s up…
Man 1: Whoaaa (wuzzam or what’s up)
Man 2: Whoaaa na (wuzzam or what’s up with you)…
Woman: hey how you been.
Man: Whoaaa or Whoaaa na, I been good. wuzzam(what’s up) with you, how you been?