A 'super' El Niño is now super likely, leaving California bracing for impact

A “super” El Niño now has a 95% chance of developing this year as the climate pattern gains dramatic strength in the Pacific Ocean — leaving officials across California and beyond bracing for a wet and potentially destructive winter.

The National Oceanic and Atmospheric Administration’s Climate Prediction Center said Thursday that the El Niño has strengthened in the last month, and there’s a roughly 7 in 10 chance it will be the strongest such pattern since 1950.

Of the three other powerful El Niños on record during that span — in 1982-83, 1997-98 and 2015-16 — two brought above-average rain to Southern California. The 2015-16 El Niño, while very strong in the ocean, did not, though the pattern was blamed for record beach erosion along the California coast.

El Niño is a climate pattern characterized by warmer ocean waters in the central and eastern tropical Pacific, coupled with changing atmospheric conditions, in which the typical east-to-west trade winds weaken or even reverse.

That shift can put Southern California in the crosshairs of potentially potent tropical moisture, though the pattern’s effects vary by area.

A strengthening El Niño could bring the highest sea levels ever recorded to the California coast this year, raising the risk of widespread and damaging flooding.

If El Niño behaves like it typically does, Southern California would expect above-average precipitation, generally from cold-frontal storms that dip farther south than usual, according to Alexander Gershunov, research meteorologist at the Scripps Institution of Oceanography at UC San Diego.

“The forecast has been evolving over the last few months, and is honing in on a strong El Niño, and possibly an unprecedented one,” Gershunov said. “We may already be seeing some of the impacts from El Niño, because even though it’s a regional pattern in the central and eastern tropical Pacific, it’s such a huge area that warms up during El Niño that it adds a lot of heat to the global climate system.”

Added to the trend caused by human-caused global warming, “we’re basically on track to set a new global temperature record this year,” Gershunov said. “We’ve all been feeling the heat that’s associated with that.”

The average global surface temperature in July was among the hottest for that month in the modern record, which stretches back to 1850, tying the record from July 2024, according to NOAA’s National Centers for Environmental Information.

Looking forward, parts of coastal California have a higher-than-50% chance of above-average temperatures for August, the NCEI said .

Among the risks El Niño poses to California are stronger-than-usual hurricane activity in the eastern Pacific, which has sent hazardous and at times deadly high waves to the state’s shores.