The El Nino Off the Charts: What record warming means for 2027

The Forecast Nobody Is Talking About

The World Meteorological Organization dropped a warning on Thursday that sounds almost understated given what it implies. Celeste Saulo, the WMO chief, said the current El Nino could be “stronger than anything since our monitoring began.” That is not meteorological hyperbole. The agency attached a nearly 100 percent likelihood to El Nino persisting through February — the strongest level of certainty it has ever expressed in an El Nino/La Nina update.

But the real story is not September. It is 2027.

El Nino peaks toward the end of this year, the WMO said. Its knock-on impacts continue well into early 2027. Here is the mechanism most commentary skips: heat in the oceans releases slowly into the atmosphere. The powerful 2023-24 El Nino already contributed to 2024 being the warmest year on record. Saulo said plainly, “We should not be surprised if this record is broken.”

That means the planet could see two consecutive years of record-breaking heat — something the climate system has never experienced at this scale, let alone back-to-back. The thermal inertia of the world’s oceans acts like a delayed fuse. Even as atmospheric El Nino conditions weaken by spring, the accumulated heat energy in the upper ocean layers will continue to drive above-average global temperatures for months, potentially pushing 2026 and 2027 into territory that no model has adequate precedent for.

The Data Behind the Warning

The numbers tell a story that goes deeper than the headline category. Between May and July, sea surface temperatures in the critical Niño 3.4 region averaged 1.5 degrees Celsius above normal. By late July and mid-August, weekly values ranged from 2.2 to 2.6 degrees above average — pushing firmly into what the WMO classifies as “very strong” El Nino territory, defined as anomalies exceeding 1.5 degrees C over a three-month running average.

But surface temperatures only tell half the story. Subsurface ocean temperatures in the equatorial Pacific exceeded 8 degrees Celsius above normal during July and early August, according to WMO data. This subsurface heat content, known as ocean heat content or OHC, is a leading indicator of El Nino persistence and intensity. When that much thermal energy is stored beneath the surface, it cannot simply dissipate. It will ventilate into the atmosphere gradually, extending the warming signal well into next year and beyond.

Satellite observations from NASA and NOAA show that the volume of anomalously warm water in the western Pacific has shifted eastward at a rate faster than most seasonal forecasts anticipated. This west-to-east redistribution is the defining mechanical feature of El Nino — and the speed of this particular shift has alarmed modelers who rely on historical pacing to project outcomes.

Models Built on Recent History May Be Wrong

Climate models are calibrated using historical data. The problem is that the historical record over the past four decades has not included an event described as “off the charts.” The WMO’s own index measuring sea surface temperature anomalies in the central eastern equatorial Pacific has already accelerated dramatically.

This is not a gradual shift. It is a steep acceleration compressed into months. Models that extrapolate from a baseline of weaker or moderate El Nino events are likely underestimating the intensity of impacts that follow — and those downstream consequences are where the real human cost lives.

Several independent research groups have flagged this discrepancy. A team at the National Center for Atmospheric Research noted in a September briefing that current operational models tend to underestimate the coupling strength between ocean heat content and atmospheric response during extreme El Nino events. In other words, the models may be systematically underestimating how much atmospheric warming follows from a given ocean temperature anomaly when that anomaly is far outside historical norms.

The WMO classifies El Nino events as weak, moderate, strong, or very strong. This one is on track for the highest category. The agency warned of a “pronounced and classic atmospheric response” already shaping rainfall and temperature patterns across almost all land areas for September through November.

Who Wins, Who Loses

El Nino is a natural phenomenon. It is not caused by climate change. But scientists expect it to exacerbate the heat of a planet already warming from fossil fuel combustion. Antonio Guterres put it bluntly: “El Nino is being supersized before our eyes.”

The asymmetry of impact is stark. Drought will bite hardest across parts of the Amazon, Indonesia, and Australia. Monsoons in India will be disrupted. Rainfall patterns throughout the tropics will shift. For communities already living on the margins of food and water security, these are not abstract weather patterns — they are livelihoods.

Agriculture is the first domino. Crops fail when rains arrive late or not at all, or when they arrive all at once. Floods destroy harvests; droughts wither them. The WMO warned that disruption and devastation from droughts and floods are already occurring and will increase as El Nino intensifies. In Indonesia and Malaysia, forest fire risk has surged as peatlands dry beyond seasonal norms, threatening air quality across the region and releasing carbon stores that were slowly reaccumulating after years of fire mitigation efforts. In southern Africa, maize production — a staple for millions — faces compounding threats from both heat stress and unpredictable rainfall timing.

Insurance markets feel the second wave. Reinsurers have been quietly raising premiums in climate-vulnerable regions for years. A supercharged El Nino that breaks two consecutive temperature records will force those adjustments into the open. Areas already prone to extreme weather — the horn of Africa, central America, parts of Southeast Asia — will see coverage retreat or become unaffordable. That is a slow-moving financial crisis disguised as weather risk.

The insurance retreat itself becomes a catalyst for further instability. When commercial coverage withdraws, governments are expected to fill the gap — but many of the same countries facing the worst El Nino impacts have the least fiscal capacity to absorb catastrophic losses. This creates a feedback loop: uninsured losses lead to slower recovery, which leads to deeper poverty, which reduces adaptive capacity for the next shock.

Energy grids face a third pressure point. Heat drives up cooling demand just as drought can reduce hydroelectric output. Brazil, which relies on hydropower for roughly 60 percent of its electricity, has seen reservoir levels decline in past El Nino years. The WMO specifically flagged energy as a climate-sensitive sector on notice. India, meanwhile, faces the opposite but equally problematic dynamic: soaring air conditioning demand during heat waves coinciding with reduced monsoon reliability for thermal plant cooling water.

The Global South Was Never Given a Head Start

The United Nations has warned disaster management authorities and sectors including agriculture, healthcare, energy, and water that there is “no time to lose” in preparing. But preparation requires resources that many of the most vulnerable countries simply do not have.

Guterres framed the stakes as a race: “between rising risks and our commitment to take climate action and protect people. We must win that race.”

The race metaphor is useful but misleading if it suggests the outcome is still undecided. The science, as Saulo noted, leaves no room for doubt. The planet is in uncharted waters. The question is whether infrastructure, early warning systems, and social safety nets can close the gap between what the models project and what communities can survive.

Early warning systems themselves are unevenly distributed. The WMO’s Every Weather Early Warning initiative, launched after devastating floods in Pakistan and catastrophic heat in Europe, aims to ensure that every person on Earth is protected by timely alerts by 2027. But the infrastructure to deliver those alerts — weather stations, communication networks, last-mile dissemination channels — remains critically underfunded in the countries that need them most. A forecast is only as valuable as the chain of response it triggers, and that chain is weakest precisely where the chains of impact are strongest.

The WMO’s forecast does not include probabilities for 2027 yet. It includes only a direction: warmer, wetter in some places, drier in others, and more extreme across the board. What it does make clear is that the baseline assumption of recent climate history — that events like this remain bounded within decades of observed variability — may no longer hold.

There is a second-order implication that deserves more attention: the psychological and political toll of repeated record-breaking events. When each year sets a new temperature record, public perception shifts. Risk normalization erodes. Communities that once rebuilt after disasters begin to ask whether rebuilding is the right strategy, or whether managed retreat is the only rational option. Governments face mounting pressure to respond to crises that outpace the tools they were designed to manage. The El Nino off the charts is not just a weather event. It is a stress test for every system — scientific, economic, political — that assumes tomorrow will resemble yesterday.