Meagher, who arrived from Ireland three years ago, works as a unit co-ordinator for ABC local radio. On Friday night, wearing a blue dress and black jacket, she joined workmates at the Brunswick Green on Sydney Rd before walking with several colleagues to the nearby Bar Etiquette.
Friends told police she had been cheerful and enjoying herself, and about 1.30am on Saturday morning decided to walk the 500m to her home.
An ABC colleague, Tom Wright, offered to walk her home, but she said she would be fine.
At 1.45am Meagher called her brother, Michael McKeon, in Perth to ask about her father, who had recently had a stroke, news.com.au reported.
McKeon said his sister sounded a little worried, and had not answered her mobile when he tried to call her back several times. She has not been seen or heard from since.
Police have checked hospitals and taxi companies without success, and said her bank account had not been accessed. Her mobile is switched off.
Brunswick, an upmarket suburb famed for its restaurants, cafes and bars, is normally brightly lit and busy on Friday nights.
"It's a relatively busy time and a busy place, I'm told, in the early hours of Saturday morning," Potter said.
Tom Meagher said it was not unusual for his wife to stay out until 2am, but she had intended to be home before midnight and he was worried when she did not answer repeated calls. At 4am he vainly searched the streets for her.
"It's Friday night in Sydney Rd, it's busy, people have to have seen something," he told the ABC. "Somebody has to have seen Jill at some stage."