Sabrina Moss, of Neasden, north-west London, died in hospital following a double shooting at the junction of Kilburn High Road and Messina Avenue at 4.12am.
Police said she was caught in the wrong place at the wrong time after going out to celebrate her birthday with friends.
Another 24-year-old woman is in hospital.
Her injuries are not thought to be life-threatening.
Tributes to Ms Moss flooded onto social networking site Twitter, with many of her friends reporting that she had a young child.
Adjei Adu wrote: "My heart goes out to her family and the lil one she's left behind, sleep well Sabrina Moss."
Leila Hassan tweeted: "My thoughts are with your family … a beautiful young woman, mother and daughter!"
Police have arrested two men in connection with the attack.
- Anyone with information relating to this case should call Hendon Police on (020) 8358-0300 or Crimestoppers anonymously on 0800 555-111.