When the Pineapple Express is in town, the rain lasts for days. However, it’s not a cold rain and the snow level is usually quite high.
The snow that counts, that creates our annual snowpack which melts in the spring and summer to feed our rivers and reservoirs, is all at high altitude anyway. Our current statewide snowpack is at 175% percent of average for today's date, and will increase significantly with this storm. But even the lower altitude rain helps refill reservoirs to a point. More reservoirs would help even more, as would a dozen or more desalination plants. Praying for a really wet winter every 3 or 5 years is a poor plan.
Hopefully we don't have a repeat of last year, when we started with above average rain/snowfall then almost zero after December.