Baltimore police are preparing for another large-scale search for Phylicia Barnes, a teenager with metro Atlanta ties who disappeared from her half-sister’s Baltimore apartment three months ago today.

Baltimore police spokesman Anthony Guglielmi said authorities will search an area that they have investigated before.

“We wanted to dig deeper earlier, but the weather got in the way,” he said, adding that he will reveal the area as the day of the actual search gets closer.

Barnes, whose 17th birthday was in January, was visiting her half-sister in northwest Baltimore. She was visiting from Monroe, N.C., a city outside of Charlotte where she was preparing to graduate from high school a year early.

Barnes' father, Russell Barnes of Riverdale, spent time in Baltimore after his daughter disappeared. Her mother, Janice Sallis, also went to Baltimore but then moved back to Atlanta in January at her family's urging.

Investigators talk to the family daily, Guglielmi said.

Authorities have gone to North Carolina and other areas to interview people but have found no reason to go to Atlanta, Guglielmi said.

“We don’t have any evidence that she left Baltimore,” he said.

Barnes left her 27-year-old half-sister’s apartment on the afternoon of Dec. 28. Her debit card hasn’t been used, her cell phone was turned off, and her Facebook page hasn’t been updated. She also missed a flight home to North Carolina.

More than 100 detectives -- including half of the Baltimore police's homicide unit -- -- as well as Maryland State Police and the FBI had been assigned to Barnes' case. Authorities were using helicopters, cadaver dogs, and other investigative tools to try and find her.

Authorities have interviewed more than 25 so-called “persons of interest,” but no one has risen to the level of a suspect, Guglielmi said. Investigators are pursing the case as an abduction and as a homicide, he said.

“It is truly, truly a baffling case; there’s no physical evidence to drive us in a new direction,” Guglielmi said. “What we’re waiting for is the innocuous tip, a tip that seems like nothing, that breaks the case wide open.”

A Facebook page, "Pray for Phylicia Barnes," has more than 21,048 "Likes" and thousands of postings, including one from her father on Monday, which says "Staying Focused."