A strong, rapidly intensifying El Niño—with Niño 3.4 anomalies already near or above +2.8 °C in September and models projecting a peak near +3.3–4.0 °C—combined with record-high extra-polar ocean temperatures and the long-term anthropogenic warming trend, underpins trader expectations that October 2026 will rank among the top three warmest Octobers. Recent months, including the joint-hottest August on record, illustrate how El Niño-driven sea-surface warmth is elevating global anomalies, though the full surface-temperature response typically lags the Pacific peak by weeks to months. Short-term atmospheric variability, regional steering patterns, and differences across datasets (ERA5, GISTEMP, Berkeley Earth) create meaningful uncertainty around whether the month edges into first, second, or third place versus fourth or lower. Seasonal outlooks from WMO and NOAA centers emphasize above-normal land and ocean temperatures through October–December, but monthly resolution hinges on the next several weeks of observational data.