The US Climate Prediction Center on Thursday upgraded the probability of a very strong El Niño to 81 percent for the final quarter of 2026, a sharp increase that places the developing event among the most intense in the observational record dating to 1950. Sea-surface temperatures in the central and eastern equatorial Pacific have already crossed the 1°C-above-normal threshold that defines El Niño, with some zones reaching 2.7°C above average last week. The agency now assesses a 97 percent chance that the phenomenon persists into early 2027, effectively ruling out a return to neutral conditions before spring.

The mechanism is well understood: anomalous warming of the tropical Pacific alters atmospheric circulation, shifting rainfall belts and weakening trade winds. This injects energy into storm systems, supercharging cyclone formation in the eastern Pacific while increasing wind shear that suppresses Atlantic hurricane activity. Mexican meteorological officials project 18 to 21 named storms in the Pacific this season, against 11 to 15 in the Atlantic. Longer-range models flagged by European forecasters suggest the amplified El Niño could disrupt the polar vortex during the northern winter of 2026-27, raising the odds of colder, snowier conditions across parts of the United States, Canada and Europe.

Regional impact assessments are sharpening. In Latin America, analysts at Morgan Stanley warn that a very strong event could add up to 168 basis points to Brazilian inflation, 132 in Colombia and 209 in Peru, driven by crop damage and energy-price pressures; Mexico’s central bank faces a similar, if more moderate, transmission channel. Viewed from Washington, the signal for the US South is a wetter winter, while California emergency planners are bracing for the kind of flash floods and landslides that accompanied previous super El Niños. India’s power ministry reports that hydroelectric output has already fallen 21 percent year on year, forcing greater reliance on coal as reservoirs deplete. Australian authorities are on watch for drought and elevated wildfire risk. In Brazil, the Espírito Santo state audit court has issued 50 preventive recommendations covering medicine stockpiles, school climatisation and water-supply contingency plans, while Rio de Janeiro’s fire service has activated a drought and forest-fire response framework.

Governments are moving from monitoring to operational readiness. Mexico’s president announced that a cell-broadcast alert system for meteorological emergencies will be operational within two months, and command posts are being installed in all 17 coastal states. The next factual milestone is the September-October peak of the Pacific hurricane season, which will test early-warning infrastructure. Beyond that, attention turns to the December-January window, when the El Niño is expected to reach maximum intensity and the polar vortex becomes susceptible to disruption, a sequence that will determine whether the economic and humanitarian costs of this event approach those of the 1997-98 episode.