Scientists are increasingly warning that a “mega” El Niño could form in 2026–27 and might be among the strongest on record, potentially comparable to the devastating 1877–78 event. Forecasters say unusually warm Pacific Ocean temperatures—possibly topping 2.5°C above normal in parts of the central and eastern Pacific—combined with the background of human-driven climate change are driving models toward alarming outcomes. Meteorologist Ryan Maue has described researchers monitoring each forecast update as “getting heart palpitations.”
The 1877–78 El Niño led to widespread drought, crop failures and famine in many regions, with mortality estimates that were extremely high for the time. If a comparable event occurred today, scientists warn impacts could be severe and widespread: intense heatwaves and extended drought across vulnerable areas such as parts of Asia and Australia; heavy rains, storms and flooding in other regions including parts of the southern United States; and major disruptions to agriculture, fisheries and supply chains that could threaten food security and economic stability.
El Niño is a natural climate pattern that arises when sea surface temperatures in the central and eastern tropical Pacific become unusually warm, altering global weather patterns. A “mega” El Niño denotes an exceptionally strong version of that pattern, with larger sea surface anomalies and amplified worldwide effects. While forecasters can detect El Niño months in advance, predicting its exact intensity remains uncertain.
If current model projections hold, governments, farmers, humanitarian organizations and infrastructure planners may need to accelerate preparations—strengthening water and food security plans, disaster-response capacity and climate-resilient infrastructure—to reduce harm from potentially extreme weather and supply disruptions.
