El Niño Could Reach Historic Strength

NOAA’s Climate Prediction Center said on May 14 that El Niño is likely to emerge in the next few months, raising the prospect of another climate pattern that can reshape heat, rainfall and storm tracks well beyond the tropical Pacific. The agency put the odds of El Niño forming in May-July 2026 at 82% and said it is likely to persist through the Northern Hemisphere winter, with a 96% chance in December 2026-February 2027. NOAA said confidence has increased since last month, but it also said peak strength remains uncertain. The forecast matters for New York City because city agencies already plan around coastal flooding, heavy rain and extreme heat risks that climate officials say are growing. ### What exactly did NOAA forecast on May 14? The Climate Prediction Center said on May 14 that “El Niño is likely to emerge soon,” with an 82% chance during May-July 2026. The agency said ENSO-neutral conditions are still present now, meaning El Niño has not officially formed yet. NOAA said the pattern is likely to continue through winter 2026-27, assigning a 96% probability for December 2026-February 2027. (cpc.ncep.noaa.gov) The agency’s forecasters said the latest weekly Niño-3.4 index was plus 0.4 degrees Celsius, while subsurface temperatures across the equatorial Pacific have been rising for six straight months. ### How strong could this El Niño become? NOAA’s strength outlook said the range of outcomes still runs from neutral conditions to a very strong El Niño. The agency said no single strength category currently has a probability above 37%, underscoring how much uncertainty remains about the peak. The official strength table issued in May shows the odds rising later in 2026. (cpc.ncep.noaa.gov) For November-December-January, NOAA assigned a 37% chance to a very strong event, defined there as an index of at least 2.0 degrees Celsius, and a 30% chance to a strong event in the 1.5 to 2.0 degree range. ### Why would New York City pay attention now? (cpc.ncep.noaa.gov) New York City’s climate agencies say the city is already exposed to tidal flooding, sea level rise, more intense storms and extreme heat even as long-term adaptation projects are built. The Mayor’s Office of Climate and Environmental Justice says neighborhood coastal protection projects are meant to reduce exposure to storm surge and tidal flooding, but cannot remove all risk entirely. (cpc.ncep.noaa.gov) The New York City Comptroller’s climate dashboard says nearly 2.5 million New Yorkers live in the 100-year floodplain. The same city materials say coastal storms, heavy rains and heat are expected to become more severe or frequent as the climate warms. ### Does El Niño automatically mean floods or heat waves in the city? (nyc.gov) NOAA says El Niño does not guarantee a specific local outcome. The agency said stronger El Niño events “do not ensure strong impacts” and only make some impacts more likely, with effects depending on season and region. NOAA’s broader ENSO guidance says El Niño’s U.S. impacts are generally clearer in winter than in summer. (comptroller.nyc.gov) Climate.gov says El Niño and La Niña have weaker impacts during Northern Hemisphere summer, and NOAA analyses of past winters show wetter-than-normal conditions were most pronounced from the Mid-Atlantic into the Northeast during the last El Niño winter. ### Why does heat stay part of this story even if El Niño is a Pacific pattern? (cpc.ncep.noaa.gov) New York City’s heat agencies say extreme heat is already the city’s deadliest weather hazard. The Mayor’s Office of Climate and Environmental Justice says more than 500 heat-related deaths occur on average each year in the city, and the Health Department’s latest mortality report estimated 525 annual heat-related deaths in the 2018-2022 period. (climate.gov) The city’s emergency guidance says heat planning should start before extreme conditions arrive, including checking cooling options and making a heat emergency plan. That means any climate signal that could tilt odds toward hotter periods is likely to draw attention from agencies already tracking neighborhood heat vulnerability and near-real-time heat illness. ### What should readers watch next? (nyc.gov) June 11, 2026, is NOAA’s next scheduled ENSO Diagnostic Discussion. The Climate Prediction Center said oceanic and atmospheric conditions are updated weekly, and those updates will show whether warming in the Pacific and the atmosphere couple strongly enough for El Niño to officially take hold. (cpc.ncep.noaa.gov) (nyc.gov)