Kay made eye contact with the victim and walked around the car park "peering into vehicles still with his shorts below his buttocks".
Court documents stated the defendant's T-shirt was also "tucked up", increasing the amount of skin on show.
After doing the rounds of the stationary vehicles, he approached the victim's car and remained about 2m away, genitals on display.
When police spoke to Kay he declined to comment.
Two years earlier the defendant had put on a similarly lewd exhibition.
On that occasion, Kay committed the public indecencies while watching two women in a nearby car.
Police arrived to find him relieved of his lower layers. He told them he was "airing himself out".
Kay, who has another flashing conviction from 1994, was banned from using alcohol and non-prescription drugs for the duration of his sentence, and was ordered to undertake any programmes as directed by Probation.
Judge Robinson accepted the defendant was a repeat offender but declined the Otago Daily Times photo application because of the man's mental health issues.