Recent observations show the 2026–27 El Niño already at exceptional strength, with weekly Niño 3.4 sea surface temperature anomalies reaching +3.2°C in late September and daily values surpassing the 2015–16 record by mid-September. NOAA’s Climate Prediction Center assigns an 83% probability that the October–December Relative Oceanic Niño Index (RONI) will exceed +2.5°C—higher than any event since 1950—driven by record subsurface ocean heat content, repeated westerly wind bursts, and a deepened thermocline. Multi-model ensembles project a peak monthly anomaly near 3.7–4.1°C in November or December, with every run exceeding prior records and strong-to-very-strong conditions likely persisting through March 2027. The next CPC update is scheduled for November 12.