WMO calls for urgent act to limit health risks of El Niño

Countries and communities across the world must take action now to prepare for increased health risks due to the strengthening El Niño, which is set to trigger more extreme heat, flooding and drought.

El Niño is forecast to intensify into a very strong event by the end of the year, with cascading impacts on economies and societies, according to the latest update from the World Meteorological Organisation (WMO). The effects are already visible in climate-sensitive sectors such as health.

“This El Niño is a test. We have the science. We have advance warning. And we still have time to act,” said WMO Secretary-General Celeste Saulo at an event during the United General Assembly in New York.

“El Niño begins with warming in the tropical Pacific, but its consequences are not limited to the Pacific. Thousands of kilometres away, El Niño can shift rainfall patterns and increase the likelihood of extreme temperatures. In cities already struggling with heat, the effects reach inside homes, workplaces, schools and hospitals,” she told the event on Urban Heat Resilience.

Celeste Saulo called on governments, health authorities and community organizations to work with meteorological services to “treat extreme heat as the predictable public-health risk that it is.”

WMO is working with partners to strengthen climate services for health. This means building the needed bridges between health and meteorological communities, to ensure that forecasts reach health authorities at the right time, and in the right format to save lives.

As El Niño peaks late in 2026, much of the Southern Hemisphere, southern Africa, South America and Australia will move into their hottest season in the first months of 2027. Their seasonal heat will land on top of El Niño, raising risks of drought, wildfires, smoke and the air pollution that follows.

City dwellers are especially vulnerable because buildings and roads absorb heat during the day and release it slowly at night. This can leave older people, children, outdoor workers, people with chronic illnesses and residents of poorly ventilated housing with little opportunity to recover.

Heat exposure directly impacts the functioning of the human body and can also contribute to death and severe illness by exacerbating cardiovascular, respiratory, renal, metabolic and mental health conditions. In many parts of the world, heat-related illness, respiratory disease linked to wildfire smoke and poor air quality will also be a concern.

Warmer temperatures and changing rainfall patterns can increase the spread of diseases carried by mosquitoes, such as malaria, dengue, chikungunya, yellow fever and Zika. In some areas, these diseases may spread into places where they have not traditionally been seen, including higher-altitude regions