A weather specialist has explained what the arrival of El Niño could mean after officials confirmed the climate pattern is now underway.
The National Oceanic and Atmospheric Administration has announced that an El Niño phase has officially begun, upgrading its alert to an El Niño Advisory on 11 June 2026 after oceanic and atmospheric conditions shifted into the pattern.
The agency also said there is a 63 percent likelihood that this episode could become ‘very strong’, sometimes referred to as a ‘Super El Niño’.
It further cautioned that it may ‘rank among the largest El Niño events in the historical record going back to 1950’.
Forecasters expect the pattern to continue through the Northern Hemisphere winter of 2026-27, with NOAA saying El Niño is very likely to persist into early 2027 and shape seasonal weather risks in many parts of the world.
So, what exactly is El Niño, and why does it matter for weather around the world?
El Niño is one half of a wider climate cycle, with the other phase known as La Niña, meaning ‘the boy’ and ‘the girl’ in Spanish.
The phenomenon is linked to sea surface temperatures and changes in winds over the tropical Pacific. When waters in the central and eastern equatorial Pacific become warmer than average for a sustained period, and the atmosphere responds, it signals El Niño. The larger system is called the ENSO phenomenon, short for ‘El Niño Southern Oscillation’.
Put simply, the oceans play a major role in shaping global weather. Water evaporates from the sea, forms clouds, and helps drive rainfall, storms and many other atmospheric conditions.
In reality, though, the system is far more complex, and El Niño can influence a broad variety of weather outcomes by shifting tropical rainfall patterns and altering the position and strength of the jet stream.
It does not directly create weather events in the same way a hurricane or heatwave does. Instead, it changes background conditions in ways that can make extreme weather more frequent or more intense, while also changing the odds of where those extremes are most likely to happen.
That can lead to many different consequences, from droughts and wildfires to flooding and hurricanes, with the common thread being an increased risk of severe weather in some regions and altered storm tracks in others.
The exact effects vary depending on where you are. Typical El Niño patterns are linked to drier conditions in parts of northern South America, including areas around the Amazon Basin, while parts of the southern US often tilt wetter than average during winter. NOAA says the strongest and most reliable US signal tends to be a more active southern storm track, which can raise the chances of wetter conditions from California across the Gulf Coast and into the Southeast, while some northern areas more often turn milder and less stormy.
Mexico can also be affected, and the pattern does not guarantee the same outcome every time. Scientists stress that El Niño shifts the odds rather than dictating a single result, which is why local forecasts can still differ from the historical pattern.
That point matters because even strong El Niño events do not always produce identical impacts. NOAA has noted that some past strong episodes brought less rain than expected to parts of the southern US, showing that the relationship is important but not absolute.
Although El Niño is a natural event and there is no evidence climate change causes it, researchers say global warming may worsen its effects. Higher global temperatures already raise the chances of extreme weather, and El Niño can add extra heat and moisture to the climate system, increasing the potential for damaging heat, intense rainfall and marine heatwaves.
Celeste Saulo, secretary general of the World Meteorological Organization, warned that a strong El Niño could ‘exacerbate drought and heavy rainfall and increase the risk of heatwaves both on land and in the ocean’.
The WMO has also said that while there is still uncertainty about exactly how strong the event will become, most forecast models now point to at least a moderate El Niño, with the possibility of a strong episode later in 2026. That means governments, farmers, emergency planners and energy markets will be watching closely for signs of flooding, water shortages, crop stress and elevated wildfire danger as the event develops.