What to know about the predictions for a potentially record-breaking El Nino

Seasonal models are predicting an El Nino climate pattern that could be the strongest on record, bringing with it more extreme weather.

“I think we’re going to see weather events that we’ve never seen in modern history before,” WFLA-TV Chief Meteorologist and Climate Specialist Jeff Berardelli, in Tampa, Florida, said Friday.

An El Nino event is expected to develop from the middle of this year, impacting global temperature and rainfall patterns, according to the World Meteorological Organization. While the models indicate that this may be a strong event, the WMO cautioned that the models also have a harder time making accurate forecasts in the spring.

What El Nino is

El Nino is a cyclical and natural warming of patches of the equatorial Pacific that then alters the world’s weather patterns. Its counterpart, La Nina, is marked by waters that are cooler than average.

Berardelli said an El Nino event essentially redistributes heat on Earth. Currently, the subsurface heat in the Pacific is moving east across the ocean and ascending to the surface from the deep waters, the initial stages of El Nino.

The WMO's Global Seasonal Climate Update showed that sea-surface temperatures are rising rapidly. There is high confidence in the onset of El Nino, followed by further intensification in the months to follow, according to Wilfran Moufouma Okia, chief of climate prediction at WMO.

El Nino typically occurs every two to seven years and lasts around nine to 12 months, WMO said.

Why it’s causing alarm

It looks like the predictive models are onto something, said California Institute for Water Resources climate scientist Daniel Swain. That is because the volume and the intensity of the subsurface warm water anomalies — or pulses of unusually warm water that are a key part of El Nino physics— are about as large as we’ve seen in the historical record, he added.

The very strongest events are called “super El Ninos.”

“One of the key building blocks to make it fully materialize is, in fact, occurring,” Swain said Friday. “We still don't know exactly what's going to happen. It's not guaranteed it'll be a super El Nino. But the potential is there for something genuinely remarkable.”

If the Pacific releases a lot of heat, it supercharges the climate system and wreaks havoc weather-wise, Berardelli said. With more heat, there will be stronger heat waves, worsening drought in some areas, but also more moisture in the air that leads to more intense floods, he said.

El Nino also subdues the hurricane season in the Atlantic because there is so much heat in the Pacific that outcompetes the Atlantic, Berardelli added. Places like the Caribbean will be extra dry this summer and likely have fewer tropical systems, he said.

Where we may see the impacts

El Nino has global impacts. Across the United States, it looks like this summer will be hotter than normal, with significant heat waves, Berardelli said. While the specifics are hard to pinpoint this far out, Berardelli is also expecting to see more frequent daily thunderstorms in the Southwest U.S.

Forest degradation, driven by wildfires, logging and drought, affects about 40% of the Amazon. This could be exacerbated in 2026 with a strong El Nino.

The excess heat brought to the surface by El Nino, combined with the planet's warming due to climate change, will lead to record-breaking global warmth, Swain said. He expects to see record global warm temperatures later this year, next year or both.

“All indicators are, at this point, that the next year is going to be a pretty wild year from a global climate perspective,” Swain said.

Michael Mann, a University of Pennsylvania climate scientist, said that while El Nino boosts global temperatures a bit for a year or two, it’s basically a “zero-sum game." It typically oscillates back toward La Nina, which in turn lowers global temperatures for a year or two, he added. The thing to worry about is the longer-term, steady warming trend that will continue as long as people continue to burn fossil fuels, Mann said Friday.

Associated Press News Director Peter Prengaman contributed to this report.

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