From devastating floods in Peru and Ecuador to droughts in Colombia and Central America, El Niño is one of the world’s most powerful climate phenomena. Now, scientists are warning that the 2026–2027 event could become one of the strongest ever recorded.

For millions of people across Latin America, the name El Niño is associated with extreme heat, destructive floods, water shortages and agricultural losses.

But what exactly is El Niño, and why can a change in ocean temperatures have such a dramatic impact on entire countries?

The answer begins in the Pacific Ocean, where a naturally occurring climate phenomenon has the power to disrupt weather patterns around the world.

And with El Niño strengthening in 2026, scientists are increasingly concerned about what the coming months could bring.

What Exactly Is El Niño?

El Niño is a natural climate phenomenon that occurs when surface waters in the central and eastern tropical Pacific Ocean become unusually warm.

Under normal conditions, strong trade winds push warm ocean water westward toward Asia. This allows colder, nutrient-rich water to rise from deeper parts of the ocean along the Pacific coast of South America.

During El Niño, those trade winds weaken, allowing unusually warm water to spread eastward.

This warming changes atmospheric circulation, influencing where clouds form, where rain falls and how temperatures behave across different regions.

El Niño is part of a larger climate cycle known as the El Niño–Southern Oscillation (ENSO), which has three phases: El Niño, La Niña and neutral conditions.

These cycles occur irregularly, typically every two to seven years. Individual El Niño events often last around nine to twelve months, although some persist longer.

The phenomenon gets its name from Peruvian fishermen, who noticed unusually warm coastal waters around Christmas. El Niño means “the little boy,” historically referring to the Christ Child.

Why Is Latin America So Vulnerable?

Latin America’s geography makes it particularly sensitive to El Niño.

The region stretches from tropical rainforests and Caribbean coastlines to the Andes Mountains, the Amazon Basin and the agricultural plains of Argentina.

Changes in Pacific Ocean temperatures can alter rainfall and atmospheric circulation across these very different environments.

What makes El Niño especially challenging is that it doesn’t affect every country in the same way.

While some communities experience torrential rain and flooding, others face months of unusually dry weather.

And those contrasting conditions can occur during the same El Niño event.

Peru and Ecuador: Heavy Rainfall and Flooding

Among the countries most directly exposed to El Niño are Peru and Ecuador.

Warmer coastal waters can contribute to intense rainfall, river flooding and landslides, particularly along their normally dry Pacific coastlines.

Roads, homes, crops and infrastructure can suffer serious damage.

Northern Peru and coastal Ecuador have historically experienced some of the most dramatic rainfall increases during major El Niño events.

In severe cases, flooding can isolate entire communities, destroy bridges and force thousands of people from their homes.

The fishing industry can also suffer as warmer waters disrupt marine ecosystems.

Colombia and Venezuela: Heat and Water Shortages

While Peru and Ecuador may experience heavy rainfall, Colombia and Venezuela often face a different problem.

El Niño is frequently associated with hotter and drier conditions across northern South America.

In Colombia, reduced rainfall can lower reservoir levels, affecting drinking water supplies and hydroelectric power generation.

Because Colombia depends heavily on hydropower, prolonged dry conditions can place additional pressure on the country’s electricity system.

Drought and higher temperatures can also increase the risk of wildfires, particularly in vulnerable forested and agricultural regions.

Venezuela faces similar risks, including pressure on water resources and electricity generation.

However, local conditions can vary, and individual regions may still experience heavy rainfall during an El Niño event.

Brazil: Drought in the Amazon, Flooding in the South

Brazil is one of the clearest examples of how El Niño can produce contrasting weather conditions within the same country.

In northern Brazil, particularly parts of the Amazon Basin, El Niño is often associated with reduced rainfall and higher temperatures.

Lower river levels can disrupt transportation, isolate communities and affect access to food and medical supplies.

Drier conditions can also increase wildfire risks.

Meanwhile, southern Brazil frequently experiences above-average rainfall during El Niño events, increasing the potential for river flooding and agricultural damage.

For a country as large as Brazil, these contrasting conditions can create significant challenges for emergency planning and economic activity.

Central America: A Growing Threat to Agriculture

El Niño can be particularly damaging in Central America, where many communities depend on agriculture.

Guatemala, Honduras, El Salvador and Nicaragua are vulnerable to rainfall shortages, especially in areas known as the Central American Dry Corridor.

This region is already susceptible to recurring droughts and unpredictable rainy seasons.

During El Niño, reduced rainfall can affect crops such as corn and beans, two essential staples for millions of families.

Small-scale farmers are particularly vulnerable because many depend on seasonal rainfall rather than irrigation systems.

Crop failures can reduce household incomes, increase food insecurity and contribute to migration pressures.

The effects can be especially serious for communities already facing poverty and limited access to resources.

Argentina, Uruguay and Paraguay: More Rain Isn’t Always Better

In southeastern South America, El Niño often brings wetter-than-average conditions, particularly during the Southern Hemisphere’s spring and summer.

For agricultural producers in Argentina, Uruguay and Paraguay, additional rainfall can sometimes be beneficial after periods of drought.

However, excessive precipitation can create problems of its own.

Flooded farmland, damaged roads and delayed harvests can disrupt agricultural production and transportation.

Heavy rainfall can also raise river levels and threaten communities located in flood-prone areas.

The economic impact depends largely on when the rain arrives, how much falls and which crops are being grown.

Scientists Warn the 2026–2027 El Niño Could Be Historically Strong

The latest forecasts are raising concerns about what could happen over the coming months.

On October 8, 2026, the U.S. National Oceanic and Atmospheric Administration (NOAA) confirmed that El Niño was continuing to strengthen.

According to NOAA, there is an 83% probability that the event will reach or exceed a historically exceptional threshold during October through December 2026, based on its Relative Oceanic Niño Index.

The agency also expects strong to very strong El Niño conditions to remain likely through January–March 2027.

The World Meteorological Organization has issued a similarly serious outlook.

Its October 2026 forecast projects that ocean temperatures in the central and eastern tropical Pacific could reach approximately 3.7°C above the reference average during October through December, with warming expected to peak around December.

Such conditions would represent an exceptionally intense event by historical standards.

However, scientists emphasize that even a very strong El Niño does not guarantee catastrophic weather in every affected country.

El Niño changes the probability of certain weather patterns, but the severity of individual floods, droughts and storms depends on additional atmospheric and local conditions.

Latin America Is Already Experiencing Serious Weather Emergencies

Some countries are already dealing with significant weather-related challenges.

According to a September 14, 2026 report from the Pan American Health Organization (PAHO), at least eight countries or territories in the Americas had issued national or subnational emergency or alert declarations related to hazards associated with El Niño.

In Peru, authorities reported 70 deaths associated with rainfall and mudslides between December 2025 and August 2026.

The report also identified 633 healthcare facilities affected by the country’s prolonged rainfall and flooding emergencies.

In Brazil, reduced water levels in the Amazon Basin and wildfire-related air pollution have created serious public health concerns.

Meanwhile, food insecurity remains a significant challenge in Central America’s Dry Corridor, particularly in Guatemala, Honduras and El Salvador.

PAHO also warned about the potential for increased health risks associated with drought, flooding, wildfires and mosquito-borne diseases.

These emergencies highlight the region’s vulnerability, although not every weather disaster can be attributed exclusively to El Niño.

How El Niño Can Affect Food Prices

One of the most significant consequences of El Niño may be felt far from flooded streets or drought-stricken farms.

Agriculture is a major source of employment, income and exports across Latin America.

When rainfall becomes unpredictable, farmers may struggle to plant or harvest crops.

Drought can reduce agricultural yields, while flooding can destroy farmland, damage transportation routes and interrupt food distribution.

Coffee, corn, rice, beans and other important agricultural products can all be affected, depending on the region and growing season.

These disruptions can contribute to higher food prices, although the actual impact on consumers also depends on international markets, transportation costs and government responses.

For lower-income families, even modest increases in staple food prices can create additional financial pressure.

The Fishing Industry Could Also Suffer

The consequences of El Niño aren’t limited to what happens on land.

Peru is home to one of the world’s most important fisheries, particularly for anchoveta, a small fish widely used in fishmeal and fish oil production.

Normally, cold water rising from the deep Pacific brings nutrients that support marine life.

During El Niño, warmer surface waters can weaken this process, reducing the nutrients available near the surface and changing where fish populations are found.

That can disrupt fishing operations, affect catches and create economic uncertainty for coastal communities.

It is one reason why Peruvian fishermen were among the first to recognize the phenomenon centuries ago.

What About Human Health?

El Niño can create serious public health challenges.

Flooding can contaminate drinking water, damage sanitation systems and increase exposure to waterborne illnesses.

Changes in rainfall and temperature can also influence mosquito populations and the transmission of diseases such as dengue, although the effects vary by location.

Meanwhile, droughts and extreme heat can increase dehydration, heat-related illness and exposure to wildfire smoke.

Communities already facing poverty or limited access to healthcare may be particularly vulnerable.

Health authorities across Latin America are increasingly emphasizing early warning systems, emergency preparedness and the protection of essential medical services.

Is El Niño Caused by Climate Change?

El Niño is a natural phenomenon that existed long before modern industrial activity.

However, it now occurs against the backdrop of a warming global climate.

El Niño can temporarily boost global average temperatures by transferring additional ocean heat into the atmosphere.

Long-term human-caused climate change is a separate process that is raising the planet’s baseline temperature.

When the two overlap, they can contribute to particularly warm conditions.

Scientists continue to study how climate change may influence the frequency and intensity of future El Niño events.

The relationship is complex, and it would be inaccurate to claim that climate change directly causes El Niño.

What Can Latin America Expect in 2027?

The coming months will be important for governments, farmers, emergency responders and millions of families across Latin America.

In areas vulnerable to drought, water conservation, agricultural planning and wildfire prevention will be particularly important.

In regions exposed to heavy rainfall, authorities will need to monitor rivers, strengthen drainage systems and prepare for potential flooding and landslides.

The challenge is that El Niño doesn’t follow an identical pattern every time.

A country that experiences severe flooding during one event might see less extreme impacts during the next.

Seasonal forecasts can help governments prepare, but they cannot predict every storm, drought or flood months in advance.

A Climate Phenomenon That Connects an Entire Continent

For Latin America, El Niño is much more than a scientific term.

It can influence the price of groceries, the availability of drinking water, the success of agricultural harvests and the livelihoods of millions of people.

A shift in ocean temperatures off the coast of South America can have consequences stretching from fishing communities in Peru to coffee-growing regions in Colombia, farming communities in Central America and major agricultural centres in Argentina.

With scientists forecasting an exceptionally strong event into 2027, the coming months will test how effectively countries across the region can prepare for extreme and unpredictable weather.

El Niño cannot be prevented. But understanding it, monitoring its development and preparing communities for its potential consequences can make a significant difference.

And for a region as geographically and economically diverse as Latin America, that preparation has never been more important.