The drought in California is not scheduled to last forever because it is winter. The biggest problems that California has with droughts happen in the summer. There are not shortages of water, only a shortage of rainfall. In the winter, there are typical patterns of rain and these will come soon.
While even a light rain is better than nothing, California will need much more than that to end its drought. They would benefit from slow and steady rains, over a period of time. Too much rain at once will cause even more problems, like mud slides and such, as the ground will not be able to absorb the water.
Global warming is very real. Southern California is known for its warm, dry climate (coupled with its terra-type natural disasters) and definitely not for its rain. These type of climates suffer the effects of global warming more apparently then others. And even if light rain does happen to fall, it won't be enough to quell the needs and wants of such a densely populated area.
California has become so dry and arid, it is a wonder any agriculture still takes place there. The rain is a great sign and, hopefully, more will come. At least it may boost the spirits of long-term residents who must constantly ration their water usage. However, I rather doubt the drought is over.