As is often the case, after El Nino. But this McClatchey/Fresno Bee piece is an unusually good one, complete with a charticle designed for web postings.
La Niña tends to influence wetter winters around the Canadian border,
but drier conditions along the Mexican border. So Southern California
— Los Angeles and San Diego — consistently get less-than-average
rainfall when La Niña occurs. The Pacific Northwest tends to get more
storms.The midpoint between wet and dry with La Niña is about
Interstate 80 in California, said research meteorologist Kelly Redmond
of the Desert Research Institute in Reno.