Tempest is a Teen Tyrant and an evil counterpart to Aqualad.
He has not appeared in the cartoon at all. His only appearance was in issue #48 Wrong Place, Wrong Time of the Teen Titans Go! comic series. When Raven sent Killowat (misspelled as Kilowatt in this issue) to a parallel Earth, thinking that she would send him to his home universe, she made a mistake and sent him to the Teen Tyrants' universe. He was spotted by Arsenal and Tempest, and after a brief chase, Arsenal shot an arrow at Killowat, which caused bubbles to form around him and trap him. They then shocked him with some wires, which knocked him unconscious. They took the captured Titan to their base and started to interrogate him for information about the Brotherhood of Justice (in this universe, good versions of the Brotherhood of Evil. Raven, realizing her mistake, teleported the Teen Titans to the Tyrant's universe, where they fought and lost. As soon as the Tyrant's were about to cross over to the Titans' universe, Gemini (disguised as Blackfire) unveiled herself and the Brotherhood of Justice came and defeated the Tyrants. It is unknown what became of Tempest and the Teen Tyrants afterwards, but it is assumed that they were thrown in jail.
It is worth noting that Aqualad later changed his name to Tempest.