According to the JPL, CA historically is actually arid, and historically goes through periods of prolonged, mega-droughts.
When CA was first settled, en mass by Europeans, and the 1900s it was an unusual wet period comparatively to historical norms.
Some of the JPL guys think the wet period is over, irregardless of CC/AGW. Although there are those who think CC/AGW will exacerbate the issue.
Regardless, I would not want to live there. No water, no life.