First, we have seen onshore winds pick back up.
These are winds that come from the ocean and blow Inland, increasing water vapor across the Bay Area.
You've noticed this in the form of increased humidity. Your skin is not as dry, your lips are not as cracked as they have been in October.
We also have a big area of high pressure off of our coastline.
This is compressing any marine layer and forcing the fog to condense close to the ground, creating dense pockets and dropping visibility.
This pattern will continue into Sunday morning. The low sun angle this time of the year also means our fog is slow to burn off in the morning, leading to less sunshine close to the coast.