NOAA confirms El Niño onset, sees 63% chance of Pacific warming exceeding 2°C and a very strong event this winter

What is El Niño?

El Niño is a natural climate phenomenon characterized by periodic warming of sea surface waters in the central and eastern tropical Pacific, off the coasts of Latin America. It occurs irregularly every 2 to 7 years and typically lasts 9 to 12 months. The warming can range from 0.5°C to 3°C, disrupting atmospheric circulation and triggering weather anomalies worldwide.

NOAA's announcement and forecast

On June 12, the U.S. National Oceanic and Atmospheric Administration confirmed the onset of El Niño in the tropical Pacific. The agency predicts the event will intensify through the autumn, reaching moderate to strong levels, with a 63% probability that sea surface temperatures will rise more than 2°C in the monitored region. If that threshold is crossed, NOAA classifies it as a "very strong" event, an anomaly that occurs on average once every 15 years. Peak intensity is expected during the northern hemisphere winter of 2026‑2027.

“Every El Niño is different. Each is unique and leaves its own imprint on our climate.”

Global weather disruptions

Historically, El Niño brings a warmer‑than‑normal winter to the northern United States while pushing more storms and snow into the southern states, as the Pacific jet stream shifts southward. Stronger upper‑level winds suppress hurricane formation in the Atlantic basin, while weaker winds favor tropical cyclones in the eastern and central Pacific, increasing coastal flood risks along the U.S. West Coast. In the tropics, drought conditions prevail in the Amazon, Australia and Southeast Asia, while China, central Africa and the southern United States see increased rainfall and cooler temperatures. Monsoon rains in India weaken, threatening rice cultivation, and warmer conditions affect Brazil and Japan.

Marine life and fisheries

The warming ocean shifts fish migration patterns: warm‑water species move poleward and cold‑water species retreat to deeper or more northerly waters. These behavioral changes impact growth, survival and reproduction, with knock‑on effects for commercial fisheries and marine ecosystems.

Europe, Italy, and amplified extremes

Although the direct link between El Niño and European weather is less immediate, the phenomenon acts as an amplifier of extreme events. Combined with the effects of global warming, it can make heatwaves more intense and persistent across the continent, including Italy. Italian meteorologists warn that the upcoming summer and autumn could bring exceptional heat, while winter may be milder and drier in the north.

Warnings and historical context

The U.N. Secretary‑General described the phenomenon as "gasoline on the fire" of a warming world.

“El Niño will throw gasoline on the fire of a world that is already warming.”

The World Meteorological Organization had earlier announced an 80% probability of El Niño developing before September. The previous El Niño event in 2023‑2024 contributed to making 2024 the hottest year on record, and scientists warn that 2026 and 2027 could break new heat records.