El Niño Likely to Return This Summer, With Implications for Global Heat and Regional Weather
A familiar climate pattern may be on the way back
A potentially strong El Niño weather pattern is expected to emerge this summer and persist through the rest of the year, according to the latest official forecast from federal weather scientists. Forecasters estimate there is a 62% chance that El Niño will develop between June and August, a window that often marks the transition from one phase of the Pacific’s natural cycle to another.
El Niño is part of a recurring climate fluctuation, and it begins with a shift in the tropical Pacific. It occurs when trade winds weaken, allowing large volumes of warm ocean water to move from the Eastern Pacific toward the Americas. That ocean rearrangement can ripple outward, influencing temperatures and precipitation patterns well beyond the Pacific basin.
While the forecast points toward development later this year, the signal is still considered early. Even so, some scientists say the potential strength and duration make this one worth watching closely, especially given how strongly recent years have been shaped by ocean-driven heat.
Why El Niño tends to raise global temperatures
One of the most consistent features of El Niño years is their tendency to push average global temperatures higher. The hottest years on record generally occur in years when El Niño is active, because the Eastern Pacific becomes hotter than usual during these events. That extra warmth does not stay confined to the ocean surface; it becomes part of the broader global energy balance.
Climate scientist Daniel Swain of the University of California Agriculture and Natural Resources describes El Niño’s role in the global system as a kind of release valve. In his explanation, the pattern helps bring heat back out of deeper ocean layers where it has been temporarily stored. El Niño, he says, allows that “subducted heat” to be unearthed, contributing to a measurable rise in global average temperatures.
This mechanism helps explain why El Niño is often associated not just with warmer conditions, but with a sense of acceleration in the pace of heat records. When the ocean gives up stored warmth, the atmosphere is more likely to experience widespread above-average temperatures, and the odds increase that a given year will stand out in the global record.
Recent history shows how powerful the pattern can be
The world saw this dynamic play out in a major way during 2023 and 2024. A long, strong El Niño pattern helped shatter global temperature records. In 2023, the planet set a new record for the hottest year ever recorded, only for that record to be surpassed by temperatures in 2024.
Those back-to-back milestones illustrate how El Niño can amplify warmth on top of an already warming baseline. When the pattern is strong and persistent, its influence can extend across multiple seasons, affecting not only the year in which it forms but also the year that follows.
Zeke Hausfather, a research scientist at Berkeley Earth and climate research lead at technology company Stripe, says that if a strong El Niño develops, it is likely to boost temperatures in 2026 somewhat, with a particularly large effect in 2027. In his view, that could put 2027 on track to probably be the warmest year on record after 2024.
That timeline matters because it underscores how El Niño’s peak impacts can lag its initial formation. The pattern may emerge in one year and then exert its strongest global temperature influence later, depending on how ocean heat and atmospheric circulation evolve over time.
El Niño is not the main driver of long-term warming
Even as forecasters and scientists focus on El Niño’s potential return, they emphasize that it is only one part of the story behind record-breaking heat. El Niño is a natural cyclic fluctuation, and its warm phase can elevate global temperatures for a period. But human-caused global warming from burning fossil fuels remains the main reason the planet is warming.
This distinction is important for understanding why global temperature records are being challenged so frequently. Even without El Niño, last year ranked among the top three hottest years on record. That means the background level of warmth is already high, and natural variations like El Niño can push the climate system from “very warm” to “record-setting.”
In practical terms, El Niño can be thought of as an amplifier. It can intensify heat in the short term, but it does not replace the underlying trend. The baseline continues to rise due to human activity, and El Niño’s periodic boosts occur on top of that long-term trajectory.
Regional impacts can be as consequential as global heat
Beyond the global average temperature, El Niño is known for reshaping regional weather patterns. These shifts can bring relief in some places and increase risks in others. The Southern United States, for example, often sees more rain and cooler temperatures during El Niño, conditions that can help control droughts and tamp down wildfire activity.
However, the benefits are not always straightforward. A new analysis by the National Integrated Drought Information System notes that the Southwest is currently in the grip of such a severe drought that one year of wetter weather would not be enough to fully replenish reservoirs. In other words, even if El Niño tilts the odds toward more precipitation in some areas, the scale of existing deficits can be too large for a single season to erase.
At the same time, the extra global heat associated with El Niño can drive more severe droughts in other parts of the world. This is one of the paradoxes of the pattern: while it may increase rainfall in certain regions, it can also intensify drying elsewhere, depending on how atmospheric circulation responds.
Storms, downpours and drought: the “energy” factor
Scientists often describe a warmer atmosphere and ocean as containing more energy that can be expressed through extremes. Swain argues that El Niño’s most dangerous effects are tied to its regional patterns and the way it can load the dice toward disruptive weather.
In his assessment, El Niño can mean more heat waves and tangibly warmer temperatures, but the broader significance is what that added warmth can do to other forms of weather. He points to “more energy for storms, heavier downpours, more intensive droughts, more extreme wildfires” as key concerns.
That framing helps explain why El Niño is watched not only by those tracking temperature records, but also by emergency managers, water planners and communities that are vulnerable to floods, wildfire smoke, and prolonged dry spells. The pattern can influence the frequency and intensity of events that strain infrastructure and public safety systems.
What El Niño can mean for Atlantic hurricanes
On the U.S. East Coast and across the Atlantic basin, El Niño tends to make it harder for hurricanes to form in the Atlantic Ocean. As a result, El Niño years often coincide with less severe Atlantic hurricane seasons.
But scientists caution against interpreting that tendency as a guarantee of safety. El Niño offers limited protection because it only takes one major storm making landfall to cause catastrophic damage. A quieter season on paper can still include a high-impact event that defines the year for affected communities.
There is another complication: climate change has caused temperatures in the Atlantic to soar, providing more fuel for storms that do form. That means the storms that develop may have more ocean heat available to draw upon, even in a year when the overall environment is less favorable for storm formation.
It is also important to note that El Niño does not temper storms that form in the Pacific. So while attention often focuses on the Atlantic during hurricane season, the broader storm picture depends on basin-specific dynamics that El Niño does not uniformly suppress.
Rainfall shifts: potential relief, but not a reset
In places where El Niño increases the odds of rain, the pattern can be welcomed as a potential counterweight to drought and wildfire. The Southern United States often experiences more rain and cooler temperatures, which can reduce immediate fire danger and ease short-term dryness.
Yet the relationship between a wetter season and long-term water security is not simple. The analysis noting that one year of wetter weather may not refill Southwestern reservoirs highlights how drought can be cumulative. When deficits build over multiple years, it can take sustained periods of above-average precipitation to restore water storage.
In that context, El Niño is better seen as a factor that can influence a season’s direction rather than a single-event solution. Even if rainfall increases, the outcome depends on timing, intensity, and how much water is absorbed by dry soils versus captured in reservoirs.
What to watch as the forecast window approaches
With forecasters estimating a 62% chance of El Niño emerging between June and August, the coming months will be a key period for monitoring ocean and atmospheric signals. El Niño’s defining feature is the weakening of trade winds and the eastward movement of warm water toward the Americas, and those shifts can become clearer as the season progresses.
Scientists are also paying attention to what a potentially strong event could mean beyond the immediate year. Swain notes that, even though evidence is still early, it could be a significant event in 2026 and potentially linger into 2027. Hausfather similarly emphasizes that the largest temperature effects may show up in 2027 if a strong El Niño develops.
For the public, the most relevant takeaway may be that El Niño is not only about “warmer weather.” It is about how a warmer ocean can reorganize weather patterns, raising the odds of some extremes while lowering the odds of others, depending on location.
Key points in brief
Forecasters estimate a 62% chance that El Niño will develop between June and August and persist through the rest of the year.
El Niño occurs when trade winds weaken, allowing warm ocean water to shift toward the Americas.
The hottest years on record generally occur during El Niño years because the Eastern Pacific is hotter than usual.
Recent El Niño conditions helped 2023 set a global heat record, which was surpassed in 2024.
Scientists say a strong El Niño could boost temperatures in 2026 and have a particularly large effect in 2027.
El Niño is a natural cycle, but human-caused warming from burning fossil fuels is the main driver of the long-term temperature rise.
Regionally, El Niño can bring more rain and cooler conditions to the Southern U.S., while worsening drought in other parts of the world.
El Niño can reduce Atlantic hurricane formation, but it does not eliminate the risk of a catastrophic landfall, and it does not temper Pacific storms.
A warming baseline makes El Niño’s swings more consequential
El Niño has always been a powerful natural pattern, capable of shifting rainfall belts and nudging global temperatures upward. What makes its return especially consequential now is the warmer starting point of the climate system. With human-caused warming already elevating global temperatures, the additional heat released during El Niño can more easily push the planet into record territory.
At the same time, the pattern’s regional impacts can be uneven. Some areas may see beneficial rain or cooler conditions, while others face heightened drought risk, heavier downpours, or increased wildfire danger. As the summer forecast window approaches, the focus will be on how strongly El Niño develops and how long it persists, because those details can shape not only seasonal weather but also the global temperature story into 2027.