The rule for capping north, south, east, and west is that these words are capped when
they represent a “recognized” geographical region and are not capped when they simply indicate direction.
…He lives in the South.
…He lives south of the intersection of Main and Broadway.
So in California, if I say I am going to “Northern California” on vacation, you would have
an idea that I am going to be up around San Francisco. If I say I am going to “eastern California,” you would not have a clue about where I will be as we Californians have no specific reference for that term.