A rapidly intensifying El Niño, with Niño 3.4 sea surface temperature anomalies already reaching +2.0–2.7 °C in recent weeks and multi-model forecasts pointing to a very strong peak exceeding +2.9 °C during the August–October period, stands as the dominant driver elevating September 2026 global temperature odds. This event builds on long-term anthropogenic warming and follows record or near-record warmth in 2023–2025, pushing September anomalies toward or beyond prior highs measured by agencies such as NOAA and Copernicus. The roughly three-to-five-month lag between Pacific SST peaks and peak global temperature response means the developing El Niño will load the dice for elevated September readings, though exact placement among the top three months hinges on the final anomaly magnitude, inter-model spread in seasonal forecasts, and minor differences across temperature datasets. Traders appear to price in high but not certain odds of a top-three finish given the strength of the event and background trend, while acknowledging realistic paths to a lower rank if the anomaly falls short of the most aggressive projections.