Except for far northern areas, California is still much drier than normal as it goes into the rainy season. The weather remains hot and dry. The vast bulk of California water from inside the state comes from the Sierra Nevadas. Snowfall amounts there are crucial for the entire state. (California, especially the southern Imperial Valley also gets water from the Colorado River.) This drought is now the most severe in decades. Previous droughts happened when far fewer people were there.
After a 3-year period of exceptional dryness in California–which now exceeds the intensity of any other such period in living memory–prospects for meaningful rainfall and snowfall have been tantalizingly ephemeral as early-season storms have repeatedly failed to live up to their initial expectations.
However, this might change, even as weather models have maddeningly contradictory predictions.
As hard as it may be to believe after years of largely nonexistent and (at best) anemic rain events (some localized intense downpours notwithstanding), it finally does appear that a substantial precipitation event may be in the cards for a large portion of drought-stricken California.
At various points, most of these models have suggested the potential for an atmospheric river of some strength to affect some part of the California coast–though there is currently near zero agreement on its actual location, strength, timing, and (indeed) even its existence.