The 2026 El Niño posted record ocean warming in October, according to Brazil’s National Institute of Meteorology (Inmet). In the central Pacific’s Niño 3.4 region, sea-surface temperatures were 2.47°C above average for the month. In the Niño 3 region farther east, the monthly difference reached 3.56°C.
Weekly measurements also set or matched records. In Niño 3, temperatures were 3.7°C above average during the final week of October, the highest reading in a series dating back to 1981. The previous record was 3.6°C, recorded in December 1982. In the Niño 1+2 region near the coasts of Peru and Ecuador, the weekly difference reached 4.6°C, matching a record set in June 1983. Inmet notes that this area has limited influence on Brazil’s climate.
Meteorologist Leydson Dantas cautioned that monthly and weekly figures should not be compared directly because they cover different reference periods.
The phenomenon began forming in June 2026 and warmed rapidly in the following months. The World Meteorological Organization said it could become one of the strongest El Niño episodes on record. El Niño occurs when surface waters in the equatorial Pacific are warmer than usual, changing atmospheric circulation and affecting rainfall and temperatures in different parts of Brazil. The effects depend on the strength of the warming, the time of year and regional atmospheric conditions, Inmet said.
Sources: Olhar Digital.