The last El Niño was from May 2023 to March 2024. (Image credit: sarayut Thaneerat via Getty images) El Niño is forecast to return as early as May, which could bring above-normal temperatures to almost everywhere on Earth, according to a new report. El Niño events occur every two to seven years as part of the El Niño-Southern Oscillation (ENSO) natural climate cycle in the Pacific Ocean. The ENSO cycle flips between the warmer El Niño phase and the cooler La Niña phase, with neutral periods in between. El Niño periods bring elevated sea surface temperatures in the central and eastern Pacific, thereby weakening or reversing trade winds and strongly disrupting global temperatures and rainfall patterns . In a Global Seasonal Climate Update published April 21, the World Meteorological Organization (WMO) reported that El Niño is set to develop during the May to July season.…