El Niño Likely to Return This Summer, With Potential to Lift Global Temperatures and Reshape Regional Weather

A familiar climate pattern may be on the verge of returning

Federal weather scientists are forecasting the likely return of El Niño later this year, a development that can influence everything from global average temperatures to regional rainfall and storm patterns. In the latest official outlook, forecasters said a potentially strong El Niño could emerge this summer and persist through the rest of the year.

In probabilistic terms, the forecast estimates a 62% chance that El Niño will develop between June and August. While this is not a certainty, it is a meaningful signal in seasonal prediction—one that governments, water managers, emergency planners, and the public often watch closely because El Niño can tilt the odds toward certain kinds of weather outcomes.

El Niño is part of a natural cycle, but it is also arriving in a world that has been steadily warming due to human activity. That combination matters: the pattern can add to global heat and can amplify or redirect regional extremes, even as the baseline climate continues to shift.

What El Niño is, and how it forms

El Niño occurs when trade winds weaken, allowing large volumes of warm ocean water to move from the Eastern Pacific toward the Americas. In practical terms, this means the Eastern Pacific becomes hotter than usual, and that warmth can influence the atmosphere above it. Because the ocean and atmosphere are tightly linked, changes in Pacific Ocean temperatures can ripple into weather patterns far beyond the tropics.

Scientists often describe El Niño as a mechanism that helps move heat around the climate system. Daniel Swain, a climate scientist with the University of California Agriculture and Natural Resources, explained that El Niño’s role in the global system is to release heat from deeper ocean layers that has been temporarily stored there. In his description, El Niño allows that “subducted heat” to be brought back to the surface, contributing to warmer conditions in the atmosphere.

That process is one reason El Niño is closely associated with spikes in global average temperatures. It does not create the long-term warming trend on its own, but it can temporarily push global temperatures higher than they otherwise would be.

Why global temperatures often peak during El Niño years

El Niño years are commonly linked with the hottest years on record. The reason is straightforward: when the Eastern Pacific is warmer than usual, the atmosphere tends to warm as well, and global average temperature can rise. This is why scientists and forecasters pay close attention not only to whether El Niño develops, but also to how strong it becomes and how long it lasts.

Recent history offers a clear example of how influential the pattern can be. A long, strong El Niño helped shatter global temperature records in 2023 and 2024. In that period, 2023 set a new record for the hottest year ever recorded on Earth, only to be surpassed by temperatures in 2024.

Those record-breaking years illustrate the way El Niño can act as a short-term accelerator for global heat. When the pattern is strong and persistent, it can add to already elevated temperatures, increasing the likelihood of record-setting warmth.

What scientists are saying about the next potential event

While the forecast points toward a likely El Niño, scientists emphasize that the evidence is still early. Swain noted that the event could be “very significant” in 2026 and potentially linger into 2027, underscoring both the potential scale and the possible duration of the pattern if it becomes established.

Zeke Hausfather, a research scientist at Berkeley Earth and climate research lead at technology company Stripe, offered a timeline-focused view of how a strong El Niño could influence global temperatures. He said that if a strong event develops, it could boost temperatures in 2026 somewhat, but may have a particularly large effect in 2027—potentially putting that year on track to be the warmest on record after 2024.

These projections are not guarantees; they are conditional statements tied to the strength and persistence of the pattern. Still, they point to the possibility that the world could see another period in which global temperatures are pushed upward by natural variability layered on top of long-term warming.

El Niño is not the main cause of the planet’s warming

Even as El Niño can raise global temperatures, scientists stress that it is not the primary driver of the planet’s ongoing warming trend. El Niño is described as a natural cyclic fluctuation—an oscillation that comes and goes. The main reason the planet is warming is human-caused global warming from burning fossil fuels.

This distinction matters because it frames how to interpret records and extremes. El Niño can help explain why certain years are especially hot, but it does not explain why the baseline keeps rising. The underlying warming trend means that even without El Niño, global temperatures can remain exceptionally high. In fact, even without El Niño, last year ranked among the top three hottest years on record.

In other words, El Niño can add a temporary bump, but the long-term climb is driven by human activity. That combination can make extreme heat more likely and can increase the odds that a warm year becomes a record-breaking one.

Regional impacts: rainfall, drought, and wildfire risk can shift

Beyond global temperature, El Niño is known for its ability to reshape regional weather patterns. The effects are not uniform; they vary by location, season, and the strength of the event. Some regions may see beneficial changes, while others may face heightened risks.

In the United States, one commonly cited effect is in the southern part of the country. During El Niño, the Southern United States often experiences more rain and cooler temperatures. Those conditions can help control drought and reduce wildfire activity by increasing soil moisture and lowering heat stress.

However, the relationship between a wetter season and long-term water recovery can be complicated. The Southwest, for example, is described as being in the grip of a severe drought. A new analysis by the National Integrated Drought Information System indicates that one year of wetter weather would not be enough to fully replenish reservoirs. That means that even if El Niño brings increased precipitation to some areas, it may not be sufficient to reverse long-term deficits in water storage.

At the same time, El Niño’s added global heat can contribute to more severe droughts in other parts of the world. This is a reminder that El Niño’s impacts are not simply “wetter” or “drier” everywhere; rather, it rearranges patterns of atmospheric circulation and can intensify extremes depending on region.

Storms and downpours: more energy in the system

One of the key concerns scientists raise about El Niño is not only the warming itself, but what that warmth can do to the broader weather system. Swain emphasized that while El Niño does mean more heat waves and tangibly warmer temperatures, its regional patterns may be among its most dangerous effects.

He described a cascade of potential outcomes tied to a warmer, more energetic atmosphere: more energy for storms, heavier downpours, more intensive droughts, and more extreme wildfires. The common thread in this description is that additional heat in the climate system can influence the intensity of weather events, even if it does not determine the exact location or timing of any single storm or heat wave.

For communities, this framing matters because it moves the conversation from averages to impacts. A modest change in average temperature can still translate into meaningful changes in the frequency or severity of extremes, especially when combined with local vulnerabilities such as water scarcity, vegetation dryness, or exposure to flood-prone areas.

Hurricane implications: reduced formation odds in the Atlantic, but limited protection

El Niño can also influence hurricane conditions, particularly in the Atlantic Ocean. On the eastern side of the United States, El Niño tends to make it harder for hurricanes to form in the Atlantic, and El Niño years often coincide with less severe hurricane seasons.

But scientists caution against interpreting this 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 overall can still include a single high-impact event.

There is another important caveat: climate change has caused temperatures in the Atlantic to soar, providing more fuel for storms that do form. That means that even if El Niño reduces the number of storms, the storms that do develop may still have access to unusually warm ocean waters.

Finally, El Niño does not temper storms that form in the Pacific. That distinction is critical for understanding risk across different coastlines and island regions: a shift that suppresses Atlantic hurricane formation does not necessarily reduce storm threats elsewhere.

What to watch as the forecast evolves

Because the current outlook describes a likely development later in the year, the coming months will be a period of close monitoring. Seasonal forecasts will continue to refine the probability, timing, and expected strength of any El Niño event as new ocean and atmospheric observations become available.

For the public, the most practical takeaway is that El Niño is a pattern that can tilt the odds toward certain outcomes, not a precise day-to-day prediction. It can raise the likelihood of particular regional tendencies—such as wetter conditions in parts of the Southern United States or suppressed Atlantic hurricane formation—while still allowing for exceptions and surprises.

At the global scale, the potential for added warmth is a central concern. If a strong El Niño develops and persists, it could contribute to elevated global temperatures in 2026 and potentially have an even larger effect in 2027, as some scientists have suggested. That would come on top of an already warm climate system shaped primarily by human-caused greenhouse gas emissions.

Key points at a glance

• Forecasters estimate a 62% chance that El Niño will emerge between June and August and persist through the rest of the year.
• El Niño forms when trade winds weaken, allowing warm Pacific waters to shift toward the Americas and making the Eastern Pacific hotter than usual.
• The hottest years on record generally occur during El Niño years; a strong event can lift global average temperatures.
• A strong El Niño helped drive record global heat in 2023 and 2024, with 2024 surpassing 2023’s record.
• Scientists say a strong El Niño could boost temperatures in 2026 and potentially have a larger effect in 2027.
• El Niño is a natural cycle, but the main driver of long-term warming is human-caused global warming from burning fossil fuels.
• Regional impacts can include more rain and cooler temperatures in the Southern U.S., but severe drought in the Southwest may not be reversed by a single wetter year.
• El Niño can reduce Atlantic hurricane formation, but it offers limited protection and does not reduce storms that form in the Pacific.

A warming world makes the stakes higher

El Niño is best understood as a powerful natural variation that can temporarily amplify global heat and rearrange regional weather patterns. On its own, it does not explain the long-term warming of the planet. But when it arrives during a period of human-driven climate change, its effects can be layered onto already elevated temperatures and existing regional stresses, such as drought conditions and heightened storm impacts.

As forecasters continue to assess the Pacific in the months ahead, the developing picture will help clarify how strong the event may become and what that could mean for heat, rainfall, drought, wildfire risk, and storm behavior across different regions. The forecast is an early signal, but it is one that points toward a potentially consequential shift in the climate system later this year.