The Japan Meteorological Agency and the U.S. National Oceanic and Atmospheric Administration forecast a ‘Super El Niño’ may develop around October 2026 [1, 2].

This climatic shift matters because it historically alters typhoon formation zones. The resulting storms can be significantly more powerful, increasing the likelihood of catastrophic urban flooding, and heavy rainfall across Japan [1, 2].

On June 10, the Japan Meteorological Agency noted the re-emergence of the El Niño pattern [2]. According to the agencies, sea-surface temperatures could rise to approximately 2°C above the long-term average [1]. This heating of the ocean provides the energy necessary to intensify tropical cyclones.

Data from NOAA indicates a 37% probability that a Super El Niño will occur during the autumn and winter of 2026 [2]. While some reports suggested the phenomenon could appear as early as June, the JMA and NOAA maintain that development is most likely to occur around October [1, 2].

Masayuki Kyoda, director of the JMA’s Abnormal Weather Information Center, said that based on previous trends, El Niño events often develop and reach their peak through the winter. He said it is entirely possible for the phenomenon to persist into the winter months [1].

The agencies are monitoring the situation as the temperature anomaly progresses. The shift in atmospheric circulation often leads to unpredictable precipitation patterns, which can overwhelm city drainage systems and lead to widespread infrastructure damage [1, 2].

“Sea-surface temperatures could be about 2°C higher than the long-term average.”

A Super El Niño represents a significant deviation from normal ocean temperatures, which disrupts global weather patterns. For Japan, this increases the volatility of the autumn typhoon season, potentially forcing the government to implement more aggressive evacuation protocols and urban flood mitigation strategies to handle storms of greater intensity than the seasonal average.