The National Oceanic and Atmospheric Administration (NOAA) estimates there is a 50–60hance that El Niño will develop during the July–September period and continue beyond that.
The World Meteorological Organization (WMO) is expected to release an updated assessment this week.
What Is El Niño?
El Niño is the warm phase of a natural climate cycle known as the El Niño–Southern Oscillation (ENSO).
It occurs when trade winds weaken across the tropical Pacific, allowing warm water to spread eastward and heat the ocean surface.
That extra ocean heat is released into the atmosphere, often increasing global average temperatures by about 0.1°C to 0.2°C during a typical event.
El Niño generally occurs every two to seven years.
Why It Matters
El Niño can reshape weather patterns worldwide:
Drier conditions:
Southeast Asia
Australia
Southern Africa
Northern Brazil
Wetter conditions:
Horn of Africa
Southern United States
Peru and Ecuador
The last El Niño (2023–2024) contributed to record-breaking global temperatures, with 2024 becoming the hottest year ever recorded.
Scientists warn that if a new El Niño forms in late 2026, its full warming impact may be felt even more strongly in 2027, as the atmosphere takes time to respond.
However, experts caution that even without El Niño, ongoing climate change could still make 2026 one of the warmest years on record.
What About La Niña?
El Niño’s cooler counterpart, La Nina, recently ended after a relatively weak and short-lived phase.
La Niña typically cools the eastern Pacific and brings the opposite rainfall patterns — wetter weather in Australia and parts of Asia, and drier conditions in parts of South America.
Despite La Niña’s cooling influence, 2025 still ranked among the hottest years on record, highlighting the dominant role of long-term global warming.
New Tracking Method
NOAA has introduced a new measurement system — the Relative Oceanic Niño Index (RONI) — to better track El Niño and La Niña events.
Unlike older models that relied on historical 30-year averages, the updated approach compares Pacific temperatures relative to the rest of the tropics, offering a more accurate real-time assessment in a warming world.