Rain is falling on the Central Coast in the first of two systems to hit the area between now and the end of the weekend.
This event has the potential to drop up to 1" of rain, the second event could double that (if not more than double).
The current rain is falling along a frontal boundary moving thru the area from the NW to the SE. The rain will continue into the late evening, ending overnight. There should be a brief break most of Friday before rain resues Friday evening and continues much of Saturday.
This second event is actually two storms meeting and merging near the Central Coast. There will be an upper trough to the NW and a SW stream of moisture moving in ahead of it.
This appears to be a marginal to moderate "atmospheric river" event. That "river" is the SW stream of moisture supply which can get focused on an area and really crank up the rain potential. Some models are very bullish on this showing cumulative rain up to 6", however, the median on modeling is more like 1-3+" with some locally higher amounts on S-SW facing slopes and mountains.
Currently, there are no advisories, earlier today there were wind advisories popping on and off. It will be locally windy with this first system as S-SW winds 10-25mph precede the front moving thru the area. There are higher gusts, but there are right on the edge of advisory criteria.
I think it is entirely possible more advisories will be needed for late Friday into Sunday if modeling continues to suggest some of these 1-3" additional inches of rain. We are saturating the ground right now, so that much new rain could cause some localized flooding.