More than 560,000 homes were reported to be still without power in California as of 0506 ET (1006 GMT), according to data from PowerOutage.us.
At least six people have died in the severe weather since New Year's weekend, including a toddler killed by a fallen redwood tree crushing a mobile home in northern California, Reuters reported.
Forecasters have meanwhile warned yet another "atmospheric river" of dense, moist tropical air will clobber California on Monday with rain and mountain snow.
An NWS weather alert on Saturday warned that the cumulative effect of successive heavy rain storms since late December could bring rivers to record high levels and cause flooding across much of Central California.