While the outlook for a strong El Niño this winter looks good, one San Diego expert said it may do little to ease the drought.
Marty Ralph, a meteorologist with the Scripps Institution of Oceanography, said California's lakes and reservoirs are more than a year behind in terms of water levels, so it would take an extremely wet winter to get back on track.
He also said the effects of an El Niño event are unpredictable and precarious, pointing out past El Niños where California actually received lower-than-average rainfall.
“It’s still a bit premature to know if we’re going to have strong El Niño conditions during our wet season this winter, but the probabilities are increasing toward 80 percent or something,” Ralph said.
Ralph also said the effects of El Niño are often felt stronger in Southern California versus Northern California. While San Diego gets a lot of water from the Colorado river, the northern part of the state relies heavily on Sierra Nevada snowfall. Therefore, a wet winter for Northern California will be critical to the state's drought.
“El Niños, strong ones in particular, can produce substantially more precipitation, especially in Southern California – something like 30 percent above normal,” he said, but added that the northern part of the state usually sees just about a ten percent increase in precipitation during those same years.
Ralph, who has studied California weather for 25 years, said this summer does resemble the lead up to the strong 1997-1998 storm when heavy rains flooded our region.
But he believes it’s premature to say we’re in store for another winter like that one.
“Wishcasting doesn’t mean it won’t happen. It’s just not necessarily founded on strong quantitative basis yet,” he said.