**Current exceptionally high sea surface temperature anomalies** in the Niño 3.4 region, already reaching +3.0°C weekly by mid-September 2026 and surpassing prior records, combined with consistent multi-model forecasts for further intensification, underpin the 77.5% market-implied odds favoring a record 2026–27 El Niño. NOAA’s Climate Prediction Center reports greater than 90% probability of a very strong event (Niño 3.4 ≥ +2.0°C) peaking October–December or November–January, with 75% odds it exceeds all events since 1950 on the relative index. Ensemble projections from IRI, GFDL SPEAR, ECMWF, and others show near-unanimous support for peak anomalies of 3.4–4.6°C in many runs, well above the 2015–16 benchmark, driven by elevated oceanic heat content and westerly wind anomalies. Traders are weighting this rapid early-season strengthening and model consensus heavily, though final ranking hinges on the exact peak timing and index methodology amid inherent forecast spread.