Recent Copernicus ERA5 data showing September 2026 at 1.63°C above preindustrial levels—trailing only the record 2023 month—has driven the overwhelming 97.3% trader consensus for second-hottest on record. Sustained global warmth from long-term anthropogenic forcing, combined with residual El Niño heat release into the atmosphere, kept anomalies elevated despite a modest cooling trend late in the month relative to prior peaks. Official monitoring agencies confirm this ranking aligns with surface and satellite observations, with historical context indicating such high anomalies remain exceptional outside strong El Niño years. Minor final dataset revisions or cross-agency differences could theoretically shift placement, though current model consensus and observational consistency make that outcome improbable.