GENEVA, September 3, 2026 — The world is entering what United Nations Secretary-General António Guterres has described as a “danger zone of extreme weather” as a rapidly strengthening El Niño builds across the tropical Pacific, raising the prospect of major disruptions to rainfall, temperatures, agriculture, water supplies, ecosystems and economies well into 2027.

The World Meteorological Organization (WMO) said Thursday that El Niño is now firmly established and is expected to intensify into a very strong event during the coming months, with an exceptionally high — nearly 100 percent — probability that it will persist through February 2027. WMO said this is the most unequivocal El Niño forecast it has issued in the history of its ENSO updates, reflecting unusually strong agreement among global forecasting systems.

The phenomenon is being fueled by exceptionally warm waters across the tropical Pacific and is expected to peak toward the end of 2026. Its climate effects, however, could continue well after the oceanic event reaches maximum strength, potentially influencing temperatures and weather patterns into 2027.

Guterres warned that the emerging event is unfolding against a planet already heated by human-caused climate change.

“El Niño is being supersized before our eyes,” he said, warning that “the planet is in uncharted waters, and those waters are heating up.” He said rising sea-surface and atmospheric temperatures were placing the world in an increasingly dangerous position as extreme weather risks grow.

WMO Secretary-General Celeste Saulo said the event has the potential to deliver a major shock to communities and economies worldwide and called for an extraordinary level of preparedness, including stronger forecasting, early-warning systems and anticipatory action. WMO says it has launched an unusually large mobilization with national meteorological and hydrological services to help governments prepare for possible impacts on agriculture, health, energy, water resources and disaster management.

NOAA: Greater Than 90% Chance of a ‘Very Strong’ El Niño

The latest assessment from the U.S. National Oceanic and Atmospheric Administration’s Climate Prediction Center provides an equally striking picture.

NOAA said El Niño strengthened significantly during July, with sea-surface temperature anomalies reaching +1.4°C in the Niño-3.4 region, +1.7°C in Niño-3 and +2.9°C in Niño-1+2. Below the ocean surface, temperature anomalies reached as much as +10°C in some areas, indicating a large reservoir of excess heat beneath the equatorial Pacific.

NOAA currently estimates a greater than 90 percent chance of a very strong El Niño during the Northern Hemisphere fall and winter of 2026–27.

Even more significantly, NOAA gives the October–December 2026 period a 69 percent chance of reaching a historic level exceeding the strength of previous El Niño events in its record dating back to 1950, using its Relative Oceanic Niño Index, or RONI, benchmark.

That does not mean every country will experience catastrophic weather.

NOAA explicitly warns that even during an El Niño of exceptional magnitude, the expected regional impacts are more likely, not guaranteed. Local weather can still be influenced by other oceanic and atmospheric systems, geography and short-term weather patterns.

WMO’s global multi-model forecast presents another extraordinary signal. For September through November 2026, its ensemble projects an average Niño-3.4 sea-surface temperature anomaly of around 3.6°C, with intensification expected to peak around November and December. Different agencies use somewhat different datasets, baselines and ENSO indices, so individual temperature-anomaly figures should not be compared directly as though they were identical measurements. Nevertheless, the various forecasting systems point in the same direction: an unusually powerful El Niño is developing.

What Exactly Is El Niño?

El Niño is not a man-made weather phenomenon.

It is the warm phase of the El Niño–Southern Oscillation, or ENSO, a naturally occurring interaction between the tropical Pacific Ocean and the atmosphere.

Under normal conditions, easterly trade winds push warm surface water toward the western Pacific. During El Niño, those winds weaken and sometimes undergo significant changes, allowing unusually warm water to spread eastward across the central and eastern equatorial Pacific.

The redistribution of an enormous quantity of ocean heat alters tropical convection and atmospheric circulation. Those changes can then influence weather thousands of miles from the Pacific, shifting rainfall, temperature and storm patterns across multiple continents.

El Niño generally develops between spring and early summer and often reaches maximum intensity between November and February. Its effects on global temperature can persist after the oceanic warming itself begins to weaken.

El Niño and Climate Change: Different Phenomena, Dangerous Combination

Scientists stress an important distinction: climate change did not create El Niño.

WMO explicitly describes El Niño as a natural climate phenomenon. But the event is now taking place on a planet whose average temperature has already risen substantially because of greenhouse gases emitted primarily through the burning of coal, oil and natural gas.

That means a strong El Niño is adding natural warming and major atmospheric disruption to an already hotter global climate system.

The interaction does not mean that every heatwave, flood, wildfire or drought can automatically be blamed on El Niño. Determining whether climate change or ENSO influenced a specific disaster often requires detailed attribution studies.

What scientists can say with greater confidence is that a powerful El Niño can increase the probability of characteristic climate anomalies, while long-term global warming can intensify heat extremes and alter the background conditions in which those events occur.

A World of Contrasting Extremes

El Niño does not produce the same weather everywhere.

Some regions may become considerably drier, increasing the likelihood of drought, water shortages, crop failures and wildfires. Other areas may experience heavier rainfall and elevated risks of flooding.

WMO’s September–November global seasonal outlook indicates an increased likelihood of above-normal temperatures across almost all land areas, accompanied by rainfall patterns increasingly characteristic of a strong Pacific El Niño.

The picture is complicated further by other climate systems. WMO expects a positive Indian Ocean Dipole to develop during the September–November period, while tropical Atlantic waters are also forecast to remain unusually warm. Those systems can strengthen, weaken or redirect typical El Niño effects in individual regions.

Indonesia Battles Expanding Wildfires

Some of the feared impacts are already becoming visible in Southeast Asia.

Indonesia is confronting a severe wildfire season as increasingly dry and hot conditions create an environment in which fires can spread rapidly.

Nearly 95,000 hectares of land were affected by fires in July alone, while more than 9,000 hotspots were detected during August, according to figures reported by Reuters. Indonesian authorities have deployed tens of thousands of personnel, aircraft, water bombing and cloud-seeding operations as they attempt to contain the fires.

El Niño does not ignite forest fires by itself. Many fires are started by human activity, including land clearing. But reduced rainfall, intense heat and dry vegetation can create conditions in which fires become considerably harder to control.

Indonesia’s forestry minister warned this week that controlling the fires could become increasingly difficult as El Niño intensifies.

The country’s vast tropical peatlands are a particular concern because peat fires can burn underground for extended periods, generating enormous quantities of smoke and carbon emissions while threatening public health and wildlife.

Panama Canal Restrictions Show Economic Risks

El Niño is also becoming a global trade issue.

The Panama Canal Authority has reduced transit capacity because rainfall in the canal watershed has fallen below expectations despite the rainy season.

Beginning September 3, 2026, daily transit slots at the Neopanamax Locks are being limited to nine ships, while the Panamax Locks are initially limited to 25 daily slots. Panamax availability is scheduled to decline further to 23 daily slots beginning September 15.

The canal depends heavily on freshwater stored in its watershed to operate its locks. Reduced rainfall and declining water availability therefore have direct implications for shipping capacity.

If restrictions become more severe or prolonged, vessels may face longer waits, alternative routes and higher transportation costs, potentially adding pressure to international supply chains.

The Panama Canal Authority specifically cited reduced precipitation and measures being taken to mitigate the adverse effects of El Niño.

South Asia Faces a Difficult Monsoon

South Asia is another region facing potentially serious consequences.

The South Asian Climate Outlook Forum forecast below-normal rainfall across much of South Asia during the June–September 2026 monsoon season, particularly across central areas, while daytime and nighttime temperatures were expected to remain above normal across much of the region.

India has already experienced a substantial rainfall deficit. August rainfall was approximately 16 percent below normal, and the India Meteorological Department has forecast below-normal rainfall for September as strengthening El Niño conditions influence the late monsoon.

Extended rainfall shortages could affect major crops including rice, corn, pulses, cotton, soybean and oilseeds while reducing soil moisture, reservoir storage and groundwater replenishment.

But less seasonal rainfall does not necessarily mean less flood risk.

This distinction is particularly important across the Himalayan region.

Nepal and the Hindu Kush Himalaya: Drier Does Not Mean Safer

The International Centre for Integrated Mountain Development, or ICIMOD, warned before the 2026 monsoon that parts of the Hindu Kush Himalaya — including Nepal, Bhutan, India and Pakistan — could experience below-normal seasonal rainfall while still facing major risks from flash floods, landslides and short-duration extreme rainfall.

ICIMOD summarized the danger in a crucial way: “A below-normal monsoon does not mean a safer monsoon.”

A season can record less total rainfall than normal while still experiencing exceptionally intense rain over a few hours or days.

That combination can be especially dangerous in mountainous countries such as Nepal. Long dry periods can weaken vegetation and soil conditions, and when extremely heavy rainfall suddenly arrives, steep terrain and fragile slopes may become vulnerable to landslides, debris flows and flash flooding.

ICIMOD’s 2026 outlook also warns of elevated risks involving drought, heatwaves, water stress and wildfires while localized extreme rainfall continues to threaten communities with floods, landslides and potentially glacier-related hazards.

The organization argues that drought and flood risks can no longer be treated as entirely separate disaster-management problems because communities may increasingly face both within the same season.

For Nepal, this means interpreting El Niño as simply “less rain” would be dangerously simplistic.

Seasonal rainfall may be below normal overall while individual storms remain destructive. At the same time, prolonged rainfall deficits can put pressure on drinking water, irrigation, agriculture, forests and hydropower.

Seasonal Forecasts Cannot Predict a Specific Flood

Scientists also caution against confusing seasonal climate outlooks with short-term weather forecasts.

A forecast indicating an increased probability of below-normal rainfall across Nepal or South Asia cannot determine whether a particular river will flood on a particular day.

Nor is it scientifically justified to declare that a specific flood, landslide or glacial disaster was caused by El Niño merely because the event happened during an El Niño year.

For such decisions, authorities need short-range weather forecasts, satellite observations, rainfall measurements, real-time river gauges, hydrological models, radar systems, geological information and effective local early-warning networks.

Nepal’s Department of Hydrology and Meteorology continues to issue national seasonal outlooks as well as shorter-term weather and hydrological information. The seasonal outlook provides broad probabilities, while operational warnings remain essential for identifying immediate hazards.

The Most Important Message: Prepare, Not Panic

The growing scientific concern surrounding the 2026 El Niño is not a prediction that catastrophe will strike everywhere.

Rather, it is a warning that the global climate system is entering a period in which the probability of disruptive weather patterns is unusually high.

Governments therefore have an opportunity to act before emergencies occur.

That includes strengthening real-time river and rainfall monitoring, expanding mobile-phone warning systems, identifying communities at high risk, preparing evacuation routes, pre-positioning medicines and emergency supplies, protecting drinking-water systems, improving wildfire surveillance and preparing farmers for both water shortages and extreme rainfall.

Agricultural insurance, climate-resilient crops, emergency food reserves and better management of reservoirs and groundwater could also become increasingly important if the El Niño persists into 2027.

WMO says its goal is precisely to translate improved forecasts into early action rather than late disaster response.

The Next Few Months Could Be Critical

Scientists will now be watching the tropical Pacific closely as El Niño approaches its expected late-2026 peak.

There is still uncertainty over exactly how powerful the event will become and how its effects will interact with the Indian Ocean, Atlantic Ocean and regional atmospheric systems.

But the broad scientific signal is unusually strong.

WMO says there is a near-100 percent likelihood that El Niño will persist through February 2027. NOAA says there is a greater than 90 percent probability of a very strong event during the Northern Hemisphere fall and winter and a 69 percent chance that its October–December strength will exceed previous events in NOAA’s record dating to 1950.

What follows could influence far more than weather.

Agriculture, food prices, drinking water, energy production, public health, international shipping, wildfire risk and humanitarian operations may all be affected.

The greatest concern is that this exceptional natural climate event is developing on top of decades of human-driven global warming.

El Niño did not create climate change, and climate change did not create El Niño. But in 2026, the two are operating simultaneously.

That combination is why scientists and the United Nations are urging governments around the world to treat the coming months not as a reason for panic, but as a critical window for preparation.

The warning from Guterres is stark: the world has entered an extreme-weather “danger zone.”

How dangerous that zone becomes will depend partly on nature — and partly on how quickly governments, institutions and communities respond.