Joshua Clay was born in Brooklyn, New York, the youngest of five children. As his parents struggled to keep the family together in the slum conditions they lived in, Joshua was tempted by the lure of the streets and at the age of 17 he became a member of the Stompers street gang. Joining the army to avoid a prison term, Clay was sent to Viet-Nam. Disciplinary problems meant he was soon moved from the medi-corps and placed into the infantry as a rifleman.
One day while he was on a routine patrol, Joshua and his sergeant came across a Vietnamese village. Believing it to be an enemy camp, the sergeant began a systematic massacre of the villagers. Horrified, Joshua reacted without thought and - much to his surprise - powerful energy exploded from his hands, knocking the crazed sergeant out of action. Startled and frightened by what he had done, Joshua ran, escaping the scrutiny of the military over his new found powers.
Joshua concluded his powers came from a genetic mutation and only manifested themselves when under the emotional trauma of combat. Now he was a deserter - wanted - and he spent the next 10 years of his life living as a fugutive on the edge of the underworld. Between aimless jobs and drifting from one city to the next, Joshua pursued an interest in medicine that had been kindled by his short stint as an army medic.
Eventually, Joshua was tracked down by the woman known as Celsius, who wanted to recruit him into the new Doom Patrol. The original team had been led by her husband, Niles Caulder - the Chief. Seeing an opportunity to go home, Joshua agreed to join the new team as Tempest. His teammates in the new Doom Patrol were Celsius, Negative Woman and Robotman.
Internal arguments led to the break up of the team and Joshua returned to New York, swearing never again to utilise Tempest's power. Using his underworld connections, Joshua was soon able to secure papers establishing a new identity of himself as Jonathan Carmichael M.D. Due to his years of private study, Joshua easily passed his New York medical boards, and with funds borrowed from a loan shark, he bought an established Park Avenue medical practice. He creates a quiet respectable practice treating the rich. Robotman tracks him down and blackmails him into rejoining the team. He later retires from superheroics and becomes their physician. Joshua Clay is murdered by a deranged Niles Caulder. Dorthy Spinner finds Clay and releases the Candlemaker from his realm on the condition he resurrects Clay. He does so and kills him again.
During the Blackest Night
, Joshua was raised by a black power ring
and attacks Elasti-Woman. As a Black Lantern
he is seen controlling the weather, creating tornados and lightning.