The first half of December was very active and we are ahead of the average for the month of December, even if we didn't get any more we'd still finish the month with more than average. That said, I don't see any meaningful rain for the rest of the month at this point.
There is a ridge that covers much of Southern and Central California. Some cold front likely hit northern CA over the next few weeks, but it doesn't look like anything makes it this far south (or at least anything meaningful).
The short-term forecast features some high-pressure wedging into California. This will hold off a low-pressure center to our west. It is currently pumping in some high clouds into the area. High clouds in winter can filter the sunshine but it also acts to reflect at least some infrared radiation back down to Earth at night.
It isn't a lot but with temps in some areas flirting with freezing this can be enough to keep temps from dropping below freezing.
