Recent Copernicus ERA5 data place September 2026 at roughly 1.63 °C above the pre-industrial baseline, confirming it as the second-warmest September on record behind only 2023. Persistent anthropogenic warming combined with strong El Niño-driven sea-surface temperature anomalies sustained elevated global temperatures through the month, mirroring the record-setting summer conditions observed in August. Trader consensus at 96.8 % for second place reflects this alignment with official monthly rankings and the low likelihood of final dataset revisions altering the order. A shift to first would require an upward adjustment exceeding 0.05 °C or a downward revision to 2023 values, both improbable given multiple independent reanalyses.