For more on the forecast timing and impacts of the upcoming storm, meteorologist Armando Salvadore shared this report with clients: 

In the last 30 days, the entire state of California with the exception of far southern Ca (Riverside and Imperial county) are above average to well above in terms of precipitation and even those aforementioned are just about near average. We've seen a substantial amount of condensed water over this winter, and there's no signs of this letting up as we roll into yet another active week next week!

Below, a potent upper-level low will look to drop southward and "bowl" itself into northern/central California. Such a mid-level disturbance will allow for a surface cyclone to manifest, and crash somewhere north of Sacramento come Tuesday midday.