Scientists are warning that a powerful El Niño event is developing in the Pacific Ocean and could push global temperatures to new highs, with 2027 emerging as a leading candidate to become the warmest year ever recorded.
Long-range climate forecasts indicate that warming waters across the central and eastern tropical Pacific are on track to develop into a strong El Niño during the second half of 2026. Several forecasting models suggest the event could reach the level known as a super El Niño, a phenomenon seen only a handful of times in recent decades.
Researchers at the Finnish Meteorological Institute said ocean temperatures in key parts of the Pacific have risen rapidly in recent months and are already about one degree Celsius above normal.
El Niño is a recurring climate pattern that develops every few years when sea surface temperatures across large areas of the tropical Pacific rise above average. The phenomenon alters weather patterns around the world and tends to increase global temperatures as heat stored in the ocean is released into the atmosphere.
Its counterpart, La Niña, has the opposite effect and is associated with cooler ocean temperatures in the same region.
The previous El Niño occurred during 2023 and 2024. Conditions then shifted towards neutral and weak La Niña patterns during 2025 and early 2026.
According to projections compiled by the World Meteorological Organization, sea surface temperatures in the Niño 3.4 region of the Pacific are expected to exceed two degrees Celsius above average later this year. Events reaching that level are often classified as super El Niños.
Such episodes have historically been rare. Comparable events occurred in 1982–83, 1997–98 and 2015–16.
Current model averages indicate warming could reach around 2.7 degrees Celsius by October 2026, placing the event on a similar scale to the super El Niño recorded a decade ago.
Some forecasts go further. Researchers noted that a number of model simulations project temperature anomalies above three degrees Celsius, a level that would surpass previous observations and potentially mark the strongest El Niño since modern records began.
Climate change is also complicating comparisons with earlier events because global temperatures have continued to rise over recent decades.
El Niño events typically influence worldwide temperature averages with a delay of several months. As ocean heat transfers into the atmosphere, global temperature records often peak during the months following the strongest Pacific warming.
The World Meteorological Organization has already stated that at least one year between 2026 and 2030 is likely to become the warmest ever recorded worldwide.
While long-term warming is driven by human activity, El Niño remains the largest natural factor influencing year-to-year fluctuations in global temperature.
The effects in Finland and Northern Europe remain less certain.
Scientists said there is no consistent relationship between El Niño and Finnish summer conditions. Previous super El Niño years have coincided with both warm and cool summers in the country.
Studies suggest winters during El Niño years are sometimes linked to a negative phase of the North Atlantic Oscillation, which can increase the chances of colder conditions in Northern Europe.
Past super El Niño winters in Finland have also produced mixed outcomes. The winter of 2015–16 included a prolonged cold spell in January despite generally mild conditions, while the winter of 1997–98 featured periods of both mild and colder weather.
The analysis was published by researchers Mika Rantanen and Ilari Lehtonen of the Finnish Meteorological Institute.
HT