Hazel Shannon, who comes from Garryowen had been staying with a friend in Moyross and has not been seen since 2.41am on Saturday.
City centre Garda CCTV cameras picked her up at that time walking along Sarsfield Street in the direction of the Ennis Road.
Inspector John O’Reilly of Henry Street said: “Hazel is seen on our CCTV system walking down Sarsfield Street at 2.41 am.
“She was wearing a purple track suit with a silver lining and a silver design on the back of the track suit back. She was wearing white and pink runners,” said Insp O’Reilly.
“Hazel is five-foot-five and slim and she had her hair in a pony tail. She had been out earlier in the city with friends,” he added.
Her mother Eileen last night issued an appeal.
She said: “If any of Hazel’s friends known anything, even if told as a secret, say something and something might come from it, please God.
“Pass it on and it might get back to me and we will have something to go on to find her, please God.”
The Limerick Marine Rescue Unit along with the Bunratty Rescue unit and the coast guard helicopter yesterday concentrated searches near Sarsfield Bridge and down river on the Shannon.
Insp O’Reilly appealed to anybody who may have seen a girl matching Hazel’s description in the Sarsfield Street area of the city early on Saturday to contact Henry Street Gardaí.