The incident happened just after midnight on Sunday at an apartment complex in the 1000 block of Mariposa Avenue, fire officials said.
The victim, identified as Susan Warner, was rushed to the hospital, where she died. No other injuries were reported.
Firefighters were able to contain the blaze to the first floor unit, where the woman lived.
The cause was not yet known as of Monday, but officials said there were melted electrical components near where the fire started. Investigators believe excessive storage conditions could have contributed to the fire's intensity.
It was no disclosed whether the apartment had working smoke alarms.