At around 12:29 p.m., the woman gave a teller a note demanding money, saying she had a gun, but no weapon was seen, Menlo Park police spokeswoman Nicole Acker said.
The suspect is described as a Pacific Island female, about 6 feet tall, wearing a red Cincinnati baseball hat, sunglasses, a dark gray or black puffy jacket, gray sweatpants and white/black tennis shoes.
She was last seen on foot leaving through the side door, Ms. Acker said.
The bank is at 701 Santa Cruz Ave. at Curtis Street in downtown Menlo Park.
A San Mateo County Superior Court judge sentenced Garry Ronald Darnell, 27, on Nov. 1 to four years in state prison with 445 days credit for time served, according to the district attorney's office.
Mr. Darnell was also ordered to pay $1,170 in fines and restitution related to his conviction for robbery, grand theft, possession of methamphetamine and four other felonies in May.
Menlo Park police arrested him on Oct. 11, 2012, after a car's owner surprised him rummaging through her vehicle that night. The victim confronted the suspect, who was holding her backpack, and got shoved to the ground as he fled.
Investigators said they found methamphetamine in his possession as well as items allegedly stolen during five other automobile burglaries and thefts.
During the trial, Eric Hove, the defendant's lawyer, had suggested that police were lying about some aspects of the case, but the argument did not sway the jury. The attorney did not respond to a request for comment.