El Niño is already pushing Pacific sea temperatures past daily warm records for more than 20 days in June. Experts warn its effects could raise global heat, alter storm and rainfall patterns into 2027, and worsen coastal flooding risk even as it may reduce Atl
By the time June ends, the ocean isn’t waiting for anyone.
In the El Niño region—along the equator in the Central and Eastern Pacific—sea surface temperatures have topped daily warm records for more than 20 days in June. Scientists say those numbers are the clearest early signal yet that this year’s El Niño could become one of the strongest on record. with ripples that stretch across weather systems and into the next two years.
Kevin Trenberth. a climate scientist at the National Center for Atmospheric Research. said El Niño is “well underway. ” pointing to upper-layer ocean temperatures more than three degrees above normal. The National Oceanic and Atmospheric Administration and others expect the event to peak between November and January. but the impacts could linger well into 2027.
For the United States, the stakes are immediate and financial as well as environmental: El Niño can reshape hurricane activity, influence drought and flooding risk, and—because it arrives on top of rising seas and high tides—raise the odds of coastal disruption.
Global models may differ on exactly how strong this El Niño will be, but the ocean’s heat is already visible.
El Niño is shifting the mechanics of weather
El Niño is a naturally occurring climate cycle. When water temperatures in the El Niño region heat up, the pattern links with the atmosphere and shifts trade winds, jet streams, and other global weather systems, changing rainfall patterns and the balance between dry and wet regions.
Daniel Swain. a climate scientist with the University of California Agriculture and Natural Resources. described the connection during a June 17 WeatherWest podcast. Emily Becker. a research professor at the University of Miami’s NOAA Cooperative Institute for Marine and Atmospheric Studies. said El Niño can contribute to large areas becoming drier or wetter.
Trenberth emphasized that El Niño is not just random ocean warmth. He said it plays “a key role in moderating temperatures in the tropical Pacific Ocean,” moving warm water that builds up in the Pacific toward higher latitudes, where heat energy is released into the atmosphere as rainfall.
That matters for markets because rainfall and storm timing are a direct input into everything from agriculture to insurance losses and coastal infrastructure costs.
Record heat is one threat; storms can still form anyway
Scientists tracking the El Niño region’s upper-layer ocean temperatures expect the pattern to temporarily hike global temperatures. They say either 2026 or 2027 could become the warmest year on record.
Becker noted a crucial nuance for the U.S.: while El Niño can limit hurricanes, storms can still form. The heat in the tropical Pacific is not a guarantee of fewer hazards everywhere, even if it tilts the odds.
In California, Swain said El Niño increases the risk for what he calls an “ARkStorm”—an extreme flood scenario involving an onslaught of repeated rain over three to four weeks.
Indonesia faces a higher risk of wildfires. And around the Galapagos Islands. Becker said temperatures tend to change “a lot. ” which can reduce the upwelling of cold. nutrient-rich water and have “profound impacts” on marine life. from anchovies to penguins. El Niño has also been blamed historically for mass coral bleaching.
Yet the same cycle can bring relief in drought-stricken places. Becker said that for areas such as the southeastern U.S.—currently suffering from severe drought and wildfires—El Niño storms can replenish groundwater and diminish drought. She also said El Niño is known to help reduce the number of Atlantic hurricanes.
A June 16 report from CropMonitor.org described mixed impacts to agricultural production, explaining that some regions could see negative effects while others—including the U.S.—historically experience more positive impacts.
Becker said scientists do not treat El Niño as a surprise catastrophe. Compared to disasters that arrive with little notice. she said experts know El Niño is coming well in advance. creating an “opportunity to prepare.” She added: “Disasters are going to happen globally. but with El Niño we have a chance to understand where and when they may happen.”.
Prediction is possible, but outcomes aren’t locked
El Niño raises the odds for certain extreme weather events, but it does not guarantee them. Swain pointed to differences across past events: extreme rain events brought widespread flooding and landslides to California during El Niños in 1982-1983 and 1997-1998. but that didn’t occur during the El Niño of 2015-2016.
In other words, even when the cycle “tips the scales a bit” toward a wet pattern, a dry outcome can still happen.
Capotondi—an associated scientist with the Cooperative Institute for Research and Environmental Sciences at the University of Colorado Boulder—used a kitchen metaphor: “It is like baking a cake.” She said. “You need all the ingredients. but also a functioning oven for a predictable outcome.” She added: “We have the main ingredients. and unless the oven breaks. we should have the cake.”.
That uncertainty is a problem for planning because it forces the same communities and industries to budget for both possibilities—preparedness for floods and resilience for drought—without knowing which one will dominate.
El Niño arrives on top of warming seas and higher tides
The cycle’s impacts are also layered onto other forces: global warming, rising sea levels, and astronomical high tides.
Trenberth said there is “clear evidence” that links between larger climate patterns in the atmosphere are being altered by climate change. He pointed to jet stream and storm tracks shifting poleward over the ocean in both hemispheres.
El Niño’s warm waters are happening in the context of warmer-than-normal temperatures across vast expanses of the Pacific. Scientists say it is already increasing sea levels in the Pacific as warm water expands.
On the California coast. where climate change has pushed sea levels 6 to 12 inches higher in some locations. Swain said El Niño could prompt temporary increases of six inches or more. He added that the combined sea level rise—paired with natural tidal increases during full moons and winter storms—will lead to more localized coastal flooding.
How much warming changes El Niño’s traditional impacts remains under study, but the direction of risk is clear: the baseline is already higher.
Forecasters expect strength, but the range is wide
Becker said scientists have “a high confidence forecast” that the U.S. will see a strong El Niño this year.
Still, model forecasts remain divided on how strong, and stronger or very strong events tend to have a more profound influence than weaker ones.
Kris Karnauskas. a scientist and colleague of Capotondi’s at the Cooperative Institute in Boulder. said based on model forecasts it could be the fifth strongest since 1982. when satellites began tracking ocean temperatures. He also said: “The fuel for a big El Niño is there. ” adding that it is “a question of whether that heat bubbles up to the surface. or if it stays lurking below the surface. out of sight.”.
Swain said he sees “considerable, growing evidence” of a potentially record-breaking El Niño event.
The economic consequences can be large
A strong El Niño can have significant impacts on the global economy. Estimates for global income losses during the 1982-1983 and 1997-1998 El Niños were in the trillions of dollars.
Research by Justin Mankin, a Dartmouth geography associate professor, found that current forecasts imply the 2026-2027 El Niño could be the costliest yet.
The ocean’s heat is already doing its job—turning climate signals into weather patterns, and weather patterns into planning problems for governments, insurers, farmers, and coastal communities.
El Niño is likely to remain a hot topic throughout 2026, with effects that may last well into 2027—no longer a distant label, but a heat signature now showing up in the daily numbers.
El Niño Pacific Ocean heat NOAA climate forecasts extreme weather risk ARkStorm coastal flooding California sea levels drought hurricanes Atlantic storms agriculture impacts CropMonitor.org