(CNN) -- Tiffany Sessions is presumed dead, and she's been missing for more years than she lived, but her family and Florida authorities continue to hold out hope that they'll find the killer.
On Thursday, Alachua County Sheriff Sadie Darnell announced that authorities believe the "long journey" may be nearing its end, as it's "highly, highly probable" that Paul Eugene Rowles, a convicted sexual predator who died in prison last year, is the prime suspect in the quarter-century-old case.
In February 1989, the blond-haired, brown-eyed Sessions, a junior at the University of Florida, donned red sweatpants and a white Aspen sweatshirt, put on her Walkman and went for her routine hourlong jog down Gainesville's main street toward a dirt trail that cut through the woods. Normally, her roommate would accompany her, but on that day, she had to study and Sessions jogged alone.
The 20-year-old economics major never came back, and aside from witnesses who saw a woman resembling Sessions walking before dusk, Sessions left no trace -- no clothing, no Walkman, not even her gold Rolex watch.
Rowles lived in the area at the time, and Darnell described him as a man with a "horrible history of violent crimes against women -- murder, rape, kidnapping." While there won't likely be a DNA connection, authorities feel circumstantial evidence is overwhelming, she said.
Rowles was serving a life sentence for first-degree murder when he died last year.
Speaking before the backdrop of a wooded area in Gainesville where murder victim Elizabeth Foster's body was found in 1992, Darnell told reporters a dig was conducted a week and a half ago because the area was a known "dump site" for Rowles' victims.
Police unsuccessfully tried to interview Rowles before he died, but after his death, they gathered items from his cell, including a journal entry on a calendar that read "2/9/89" -- the date Sessions disappeared -- with "No. 2" scrawled on both sides of the notation. Police believe it's an indication that Sessions was Rowles' second victim.
"It may not be a smoking gun, but it's close," said the missing woman's father, Patrick Sessions.
According to police and the family, other factors connect Rowles to Sessions' disappearance. He delivered scaffolding to a construction project along Sessions' jogging path and didn't work the night of her disappearance, for example.
"He was in this community. He murdered in this community," Darnell said.
Darnell asked the media to distribute photos of Rowles at different points in his life, study the timeline of his life and crimes and "go back in time 25 years." She also encouraged anyone with information about Rowles -- no matter how trivial it may seem -- to call 352-384-3323. Authorities are offering $1,000 for any information leading to an arrest.
"We want to have this last piece of conclusive connection so the family can at least have some peace," the sheriff said. "There's no risk. He's dead. Thank goodness he's dead."
The missing woman's mother, Hilary Sessions, appeared at the press conference with the sheriff, at times smiling and optimistic, at other times teary. She thanked numerous people for their help over the years and conceded that police were "searching for a very small needle in a very big haystack."
Still, she clearly had hope.
"She's my masterpiece," Hilary Sessions said. "It would be nice to be able to put her to rest after all these years."
Patrick Sessions -- who, like some of the law enforcement officers on the scene, wore a baseball cap saying, "The search for Tiffany Sessions" -- encouraged anyone with the even "the vaguest information that we can use" to come forward and let authorities assess whether the information is useful.
"This is for real. This is our chance to close this case," he said.
CNN's AnneClaire Stapleton contributed to this report.