Jholie had been missing since leaving her home on Jan. 12, police said.
Fairfax County police declined to say what prompted officers to look in the location for the body, which was discovered behind a pair of tennis courts and was almost completely concealed.
Julie Parker, a spokeswoman for the Fairfax County police, said it was the second time police had searched the park for Jholie and that they had hoped to find her alive. The first search came in the days after she disappeared.
Many other questions were unanswered. Police were awaiting a cause and manner of death from the medical examiner and Parker declined to comment on a motive or possible suspects. No arrests have been made in the case.
Parker said Jholie's body has been transferred to the medical examiner's office. Police said it was unclear how long the body had been in the park, but Johlie was identified by appearance and a tattoo.
At a Friday evening press conference, Parker had to deflect questions about the department's handling of the case, which had angered Jholie's parents.
The parents said in media interviews they felt Jholie might be in danger, but they did not believe police were treating the case with urgency.
Parker pushed back on that idea. "Our understanding was that she had vouluntarily left home and there were no signs of foul play," she said.
Jholie was last seen leaving her home in the 4200 block of Sonia Court around 4:15 p.m. on Jan. 12, according to a post by her mother on Facebook.
The post said Jholie told her sister that she would be right back, but didn't text her again until 8:02 p.m. to say she was going to a party in Norfolk, Va. That was the last time she was heard from.
Cyrille Moussa, Jholie's father, told WUSA9 that Jholie received a call on Jan. 12 from a 12-year-old boy's cellphone. The father said the boy later told him a man asked the boy to borrow his phone to place the call.
Jholie was reported missing by her family the next day, police said.
Last week, Fairfax County police said they had interviewed about 20 of Jholie's friends, but many were not fully cooperating.
Moussa's family did not respond to requests for comment Friday. On a Facebook group started to help find Jholie, a relative wrote that they are processing the news.
"Please continue to pray for our family," said the relative's message.