El Niño Keeps Strengthening: CPC Puts Odds of a 'Super El Niño' Near 60%, Raising California's Wet-Winter Risk
El Niño strengthened further over the past month and now has about a 60% chance of becoming a historic "Super El Niño," the Climate Prediction Center (CPC) of the National Oceanic and Atmospheric Administration (NOAA) said in its latest ENSO Diagnostic Discussion, issued on November 12. Sea surface temperature anomalies exceeded 4.0°C across the eastern equatorial Pacific and the band of anomalous warmth extended farther west. The CPC expects a strong-to-very strong El Niño to persist through January-March 2027, with a probability of more than 79%. For California, the outlook raises the risk of a wetter, stormier winter, though the CPC stressed that such impacts are more likely, not guaranteed.
The latest observations show all of the key sea surface temperature indices climbing: the Niño-3.4 index reached +2.5°C, Niño-3 reached +3.6°C, and Niño-1+2, at the far eastern end, reached +4.4°C. Below the surface, equatorial subsurface temperatures (averaged from 180° to 100°W) remained significantly above average, with a deeper-than-average thermocline and anomalies exceeding +10.0°C at depth in the eastern Pacific, continually feeding the warm surface waters. In the atmosphere, low-level westerly and upper-level easterly wind anomalies extended across the equatorial Pacific, convection and rainfall stayed enhanced from the central to the eastern Pacific while conditions remained suppressed over Indonesia, and the Southern Oscillation indices were consistently negative. The CPC said the coupled ocean-atmosphere system reflects the ongoing evolution of El Niño, and the ENSO alert status remains an El Niño Advisory.
A "Super El Niño" refers to an event whose strength ranks at the very top of the historical record. The CPC now measures intensity with the Relative Oceanic Niño Index (RONI): if the three-month RONI value reaches +2.5°C or more, this event would exceed every El Niño dating back to 1950. The CPC's official outlook, which synthesizes models from North America and abroad, indicates El Niño will keep strengthening before beginning to weaken in early 2027, peaking this winter. The chances of reaching that historic threshold are now estimated at about 60% for both the October-December and November-January periods, still better than even odds. Notably, while the event itself is strengthening, the odds of a record-breaking outcome have eased from the 83% given for October-December in last month's discussion, and the CPC kept its language on impacts cautious: even with a very strong El Niño, the chances of experiencing impacts consistent with El Niño are higher, though not guaranteed.
For California, the main implication is on the precipitation side. Under NOAA's winter outlook, winters dominated by a strong El Niño typically run warmer across the northern United States and wetter across the southern tier, and California, especially Southern California, falls within the area tilted toward above-average precipitation, with a potentially more active subtropical jet stream bringing storms and atmospheric rivers. State, county and city agencies across California have spent months preparing, stockpiling sandbags, clearing drainage systems and declaring local emergencies in a number of jurisdictions. The CPC cautioned, however, that El Niño provides only a seasonal-scale shift in probabilities: the track and rainfall of any individual storm still depend on the weather pattern at the time, and a wet winter cannot be assumed.
The next ENSO Diagnostic Discussion is scheduled for December 10, when the CPC will update its assessment of the event's strength and probabilities.
Related: NOAA Winter Outlook: Strong El Niño to Dominate This Winter, Warmer North and Wetter South
Source: NOAA Climate Prediction Center
Published by GSM · USA (original Chinese edition)
Photo: 赤道太平洋2026年10月相对海表温度距平图：东太平洋大片海域海温偏高超过4.0°C。图：美国国家海洋和大气管理局气候预测中心（NOAA Climate Prediction Center），公共领域。Photo: Relative sea surface temperature anomalies in the equatorial Pacific for October 2026, with anomalies exceeding +4.0°C across the eastern Pacific. (NOAA Climate Prediction Center, public domain)
