A \u201csuper\u201d El Ni\u00f1o is now 95% likely to develop this year as the climate pattern gains dramatic strength in the Pacific Ocean \u2014 leaving officials across California and beyond bracing for a wet and potentially destructive winter. <\/p>\n
The National Oceanic and Atmospheric Administration\u2019s Climate Prediction Center said Thursday that El Ni\u00f1o has strengthened in the past month, and there\u2019s about a seven-in-10 chance it will be the strongest such pattern since 1950.<\/p>\n
Of the three other powerful El Ni\u00f1os on record during that span \u2014 in 1982-83, 1997-98 and 2015-16 \u2014 two brought above-average rain to Southern California. The 2015-16 El Ni\u00f1o, while very strong in the ocean, did not, though the pattern was blamed for record beach erosion<\/a> along the California coast. <\/p>\n El Ni\u00f1o is a climate pattern characterized by warmer ocean waters in the central and eastern tropical Pacific, coupled with changing atmospheric conditions, in which the typical east-to-west trade winds weaken or even reverse.<\/p>\n That shift can put Southern California in the crosshairs of potentially potent tropical moisture, though the pattern\u2019s effects vary by area.<\/p>\n In the modern historical record, past El Ni\u00f1os have never been warmer than 4.5 degrees above baseline. But there is now a 69% chance that this El Ni\u00f1o will reach or exceed that threshold in the tropical Pacific. <\/p>\n That \u201chas never happened in our historical record dating back to 1950,\u201d Michelle L\u2019Heureux, the El Ni\u00f1o team lead for NOAA\u2019s Climate Prediction Center, told The Times. <\/p>\n The last record set was during the 1982-83 El Ni\u00f1o season, where the Relative Oceanic Ni\u00f1o Index was 4.32 degrees above baseline.<\/p>\n The most powerful type of El Ni\u00f1o is officially designated as \u201cvery strong,\u201d though it\u2019s often referred to as a \u201csuper\u201d El Ni\u00f1o. Reaching that threshold requires temperatures in the equatorial Pacific to be at least 3.6 degrees above baseline. <\/p>\n For the three-month period of October, November and December, NOAA\u2019s Climate Prediction Center forecasts a 95% chance that El Ni\u00f1o will be \u201cvery strong,\u201d and a 5% chance it will merely be \u201cstrong.\u201d <\/p>\n Historically, the effects of El Ni\u00f1o on Southern California\u2019s rainfall and snowfall become more obvious from December onward, with January to March \u201cas the prime season for impacts,\u201d L\u2019Heureux said. <\/p>\n