First off, don't call me "champ": it's patronizing. Are we clear, sport?
Second, that's improper word usage, as you can see by this handy definition of the word:
v. an·nounced, an·nounc·ing, an·nounc·es
1. To make known publicly.
2. To proclaim the presence or arrival of: announce a caller.
3. To provide an indication of beforehand; foretell: The invention of the microchip announced a new generation of computers.
4. To serve as an announcer for: announce a football game on TV.
1. To declare one's candidacy: was declared the front-runner even before she announced.
2. To serve as an announcer.
Now you tell me where emphasis on the first "whoo" would fall into the definition of announce.