El Niño could be strongest ever — but can it match El Niño mania?

Average Pacifc Ocean sea surface temperature anomalies (°C) for the week of August 5th. Anomalies are computed with respect to the 1981-2010 base period weekly means. In their latest El Niño Advisory, the National Weather Service predicted a greater than 90% chance that El Niño will affect the Northern Hemisphere this winter. less Average Pacifc Ocean sea surface temperature anomalies (°C) for the week of August 5th. Anomalies are computed with respect to the 1981-2010 base period weekly means. In their latest El Niño Advisory, the ... more Photo: NOAA Photo: NOAA Image 1 of / 54 Caption Close El Niño could be strongest ever — but can it match El Niño mania? 1 / 54 Back to Gallery

The El Niño brewing in the tropical Pacific is getting really big. So is the hype.

In California, after four dry years, people are hungry for wet weather, not only prattling on about precipitation but also tracking monsoons on the Internet and schooling themselves on the fine points of the jet stream — all in hope that the climatic pattern named after a child delivers an adult-size punch of moisture this winter.

The U.S. Climate Prediction Center’s monthly update, released Thursday, fueled the enthusiasm. The agency noted that ocean conditions are on par with what forecasters saw before the monster El Niño winters of 1997-98 and 1982-83, when record storms pummeled the state.

Equatorial waters are significantly warmer than average, and trade winds that normally push tropical seas away from the Americas continue to weaken, the agency said — signals that the El Niño that emerged in March is turning into the giant associated with worldwide weather changes, including more rain in the Golden State.

“We’re predicting that this El Niño could be among the strongest in the historical record dating back to 1950,” said Mike Halpert, deputy director of the National Oceanic and Atmospheric Administration’s Climate Prediction Center.

Halpert was quick to caution that the event holds no guarantee of above-average rain and snow for California. But he said the stronger the El Niño, the greater chance that wet weather will nourish a state gripped by wildfire and water shortages.

“Conserve,” he advised, “but prepare, if you need to, for some flooding-type rains.”

At San Francisco’s Ocean Beach, where a front-row seat to the El Niño is assured this winter, surfers are increasingly indulging in conjecture about what a big event might bring.

Video: 'Godzilla El Nino' May Be Coming to California, Latest Forecast Suggests; Could Bring Once-in-a-Generation Storms

Mother Nature decides

“If it’s going to be like last time, there’s going be a lot of storms and a lot of swell,” said Ben Gulick, 30, who lives in San Anselmo but grew up surfing in the city and remembers the 1997-98 whopper of an El Niño. “It’s kind of up to Mother, though. We’ll see.”

Even if the coast does get a pounding, the quality of the waves, surfers note, will hinge on the local weather conditions, like wind and currents.

The meteorological mania isn’t restricted to the Bay Area. Commodity prices on the other side of the Pacific, where dry weather is associated with El Niño, jumped this summer amid fears of potential crop losses.

Port officials at the Panama Canal, who also blame the system for a lack of rain, announced that El Niño was drying up shipping lanes and prompting restrictions on boat size.

And some in Southern California have begun taking precautions for heavy storms, such as repairing roofs and stockpiling sandbags amid forecasts for rain.

In its report Thursday, the Climate Prediction Center stood by last month’s projection of a 90 percent chance that the strengthening El Niño will hang around through the start of next year. And it bumped up the odds of the pattern remaining until spring from 80 to 85 percent.

Photo: John Blanchard

That’s important for California because the state’s storm track commences in winter. Depending on the strength of the El Niño, the system can add moisture to fronts that typically hit the coast between December and February, potentially providing some relief from the drought.

‘The Blob’

Federal forecasters expect the event to be strong and last month pegged the chance of rain at 50 percent greater than usual in parts of Southern California, where El Niños more typically play out. But the prognosis for Northern California remains less certain.

The latest puzzler is a patch of warm water in the North Pacific, which some have dubbed “the Blob.” The stretch has been prevalent during the past few years in tandem with a ridge of atmospheric pressure that’s blamed for blocking storms from hitting California and setting the stage for the drought.

“The discussion now is what impact will this warming in the North Pacific have this year?” said meteorologist Jan Null at Golden Gate Weather Services. “Without that warm area, I’d be jumping up and down with the likelihood of above normal precipitation.”

Forecasters say “the Blob” could continue to have a role in deterring storms or at least weaken the El Niño. Or, conversely, it could be a source of moisture that reinforces a wet El Niño.

These unusually warm water temperatures have extended to California. At Ocean Beach, it’s the first thing surfers mention, whether they’re getting in the water with a thinner wetsuit or seeing more dolphins and other sea critters that are taking to the heat.

“Everyone I talk to says there’s just nothing to compare it to,” said San Francisco resident Don Reigrod, who has been surfing for more than 20 years. “I don’t know what it is … but there’s definitely something going on.”

For some, the El Niño hype carries a danger. Shortly after federal forecasters released their monthly report Thursday, state water officials responded with a media advisory of their own, pleading with Californians to temper their exuberance about what some are now calling the Godzilla or Bruce Lee of El Niños.

“California cannot count on potential El Niño conditions to halt or reverse drought conditions,” wrote state climatologist Mike Anderson.

No time to let up

State officials worry that forecasts for wet weather will prompt people to slack off on conservation measures introduced by the governor. Since June, most communities have faced state orders to reduce water use.

Even a rainy winter won’t likely make up for four dry years, forecasters say. The state would need roughly 2½ times its average rainfall, depending on the area, to patch the deficit — and even the state’s wettest years have seen just less than twice the average.

Kurtis Alexander is a San Francisco Chronicle staff writer. E-mail: kalexander@sfchronicle.com Twitter: @kurtisalexander