NOAA predicts a very strong El Niño with high odds of historic intensity and wet winter for California

The National Oceanic and Atmospheric Administration’s Climate Prediction Center upgraded the current El Niño to the “very strong” category on Thursday, indicating an 83% probability that the event will reach historic strength by early 2027, surpassing all occurrences since 1950. Key sea-surface temperatures in the central-eastern Pacific are now 2.1 °C above normal, just meeting the threshold for the highest classification.

Scientists note that the phenomenon, which began to emerge in June, has already intensified the eastern Pacific hurricane season, producing large swells that have impacted Southern California and the Hawaiian Islands. "It’s El Niño macho, as I call it," said Josh Willis, a senior research scientist at NASA’s Jet Propulsion Laboratory. "This is a big event, it’s still growing in size, and its impact is just starting to reach out of the tropics."

Meteorologists and oceanographers warn that the combination of El Niño-driven ocean warming and long-term climate change could raise coastal sea levels and increase flood risk. "Every couple inches of sea level rise doubles the risk in California in terms of flooding," said Patrick Barnard, director of research at the Center for Coastal Climate Resilience, UC Santa Cruz.

State officials have begun preparations; Governor Gavin Newsom declared a state of emergency in September to mobilize resources. Seasonal forecasts from both the Climate Prediction Center and the European Centre for Medium-Range Weather Forecasts show a 70-100% chance of above-normal precipitation across coastal California this winter, suggesting a markedly wetter season than average.

"There’s a 70 to 100% chance of a very wet winter across all of coastal California," said Daniel Swain, a climate scientist with the University of California’s Agriculture and Natural Resources group, citing the European model’s strong signal.

The outlook reflects heightened confidence as the season approaches its peak three-month period, according to Michelle L’Heureux, a physical scientist at the Climate Prediction Center.