The strongest El Niño could unfold this year, with forecasters warning the Pacific-driven pattern may rank among the most powerful seen in decades and shape weather across the United States well into next year.
El Niño forms when trade winds that usually blow east to west across the tropical Pacific weaken, allowing unusually warm surface waters to shift eastward. That warmth fuels clouds and storms over the central and eastern Pacific, which can ripple through the global atmosphere and alter weather far from the tropics.
According to AccuWeather Lead Long-Range Meteorologist Paul Pastelok, whether this episode breaks records or not, the focus should remain on consequences. “It is about the impacts and the impacts will not change either way,” he said.
Forecasters say the pattern is already tamping down Atlantic hurricane activity this season. It is expected to persist into next year, prolonging heat through fall across northern and eastern states while directing frequent, soaking storms across the southern tier of the country even as the Atlantic likely stays quieter.
Through winter, outlooks indicate the Southeast and southern Plains could face rounds of snow, sleet, and freezing rain. Florida may see more thunderstorms than usual, while parts of the Gulf Coast experience fewer, according to a CNN meteorologist.
Despite potential winter precipitation, the West’s long-running water shortfall is unlikely to see lasting relief after the most severe spring drought on record. “Even one big year is not going to save us,” said John Berggren, a policy manager at Western Resource Advocates. “It might be a sigh of relief, but we’ll be right back in it.”
Federal forecasters reported last week there is a 90 percent chance the 2026-2027 event will achieve the highest strength category. El Niño strength is typically classified on a four-step scale from weak to very strong.
How the strongest El Niño reshapes global patterns
El Niño is the warm phase of the El Niño–Southern Oscillation, a recurring climate cycle that influences temperature and precipitation worldwide every two to seven years.
Experts note that similarly powerful events are rare. The last episode of comparable intensity was in 1877, when widespread drought contributed to a global famine that killed tens of millions.
“Simultaneous multiyear droughts similar to those in the 1870s could happen again,” said Deepti Singh, an associate professor at Washington State University. She added that today’s warmer atmosphere and oceans mean any resulting extremes “could be more extreme.”
Researchers continue to study how much human-caused climate change may be affecting these events. What is clear, scientists say, is that a warming climate is elevating temperatures and can intensify storms.
This past July ranked as the hottest on record. “What we’ll see in 2027 is a sneak peek of what the new normal will be in 2035,” said Zeke Hausfather of Berkeley Earth.
“We’ll see things that have never happened before in our history in terms of temperature, drought conditions, extreme heat.” For more on how governments are weighing costly climate-related upgrades, see our coverage of the White House construction project.
For background on how U.S. agencies track these climate signals, readers can consult the National Oceanic and Atmospheric Administration.