September 2026 was western Europe’s warmest on record

September 2026 was the second-warmest September ever recorded worldwide, behind September 2023.

Western Europe had its warmest September on record, while Europe as a whole had its third-warmest.

The global average air temperature was 1.63°C above the preindustrial level, and the average sea-surface temperature reached a September record.

The preindustrial level is a reference point for comparing today’s temperatures with those before widespread industrial activity.

Temperatures were also exceptionally high across much of the tropical Pacific, where El Niño conditions are strengthening.

Copernicus said El Niño is expected to intensify further in the coming months and could become one of the strongest on record.

The report also noted that Antarctic sea ice reached its third-lowest September extent on record.