October 2026 was the warmest October ever recorded worldwide, according to new figures from the Copernicus Climate Change Service, as a record-breaking El Niño combined with human-caused climate change to drive global temperatures higher.
Global average surface air temperatures reached 15.35°C (59.63°F) during the month. That reading placed October 2026 at 1.75°C (3.15°F) above pre-industrial levels and marked the third consecutive month to breach the 1.5°C (2.7°F) global warming threshold.
Samantha Burgess, Strategic Lead for Climate at the European Centre for Medium-Range Weather Forecasts (ECMWF), said: "October has continued the pattern of remarkable global warmth, with record global and surface ocean temperatures. An exceptionally strong El Niño is adding further heat to a climate already warmed by human activities, while 2026 is on track to become the second calendar year above 1.5°C (2.7°F)."
The Copernicus Climate Change Service is the climate monitoring arm of the European Union's Earth observation programme. It is operated by the ECMWF, an independent intergovernmental research organisation based in Reading, England, that tracks global weather and climate conditions using satellite observations, ocean buoys, aircraft and ground stations.
Record ocean heat and El Niño in the Pacific
Ocean temperatures surged to unprecedented levels alongside atmospheric heat last month. The average sea surface temperature outside the polar regions reached 20.95°C (69.7°F), making it the warmest October on record for the world's oceans and passing the previous October peak set in 2023.
In the tropical Pacific Ocean, where the current El Niño continues to intensify, water temperatures climbed to levels never previously observed by scientists. Researchers recorded a temperature anomaly of 3.21°C (5.78°F) in the Niño 3.4 monitoring region, exceeding the peaks registered during the major El Niño events of 1982-83, 1997-98 and 2015-16.
El Niño is the warm phase of the El Niño-Southern Oscillation, a recurring climate pattern in the equatorial Pacific. When trade winds that normally push warm water westward toward Asia weaken or reverse, vast reserves of stored ocean heat rise to the surface in the central and eastern Pacific and escape into the atmosphere.
Climate scientists gauge the intensity of an El Niño event by measuring sea surface temperature departures from normal inside the Niño 3.4 zone, a band of the central and east-central equatorial Pacific that serves as the primary international benchmark for tracking the phenomenon.
Global temperature forecast for 2026 and the 1.5°C threshold
The Copernicus data indicates there is around an 80 per cent chance that 2026 will finish as the second-warmest calendar year on record. Scientists also estimate a roughly 20 per cent chance that 2026 could tie with or surpass 2024 as the hottest year ever measured.
Experts said the average global temperature for the full year of 2026 is virtually certain to exceed 1.5°C above the pre-industrial baseline.
The pre-industrial baseline refers to average global temperatures between 1850 and 1900, before widespread industrial fossil fuel burning increased atmospheric greenhouse gas concentrations. Under the 2015 Paris Agreement, nearly 200 countries committed to pursuing efforts to limit long-term global warming to 1.5°C above that baseline to reduce the risk of severe climate impacts.
The five hottest Octobers and European climate extremes
Every one of the five warmest Octobers in the instrumental record has occurred since 2019, measured by how far global temperatures rose above pre-industrial levels:
- 2026: 1.75°C (3.15°F)
- 2023: 1.7°C (3.06°F)
- 2024: 1.65°C (2.97°F)
- 2025: 1.55°C (2.79°F)
- 2019: 1.3°C (2.34°F)
Across Europe as a whole, October 2026 was the second-warmest October on record, with continental temperatures averaging 1.49°C (2.68°F) above the long-term average.
While parts of western Europe faced heavy rain, the Copernicus report recorded exceptionally low river flows across regions of central and eastern Europe. Those dry conditions affected major continental waterways including the Rhine, the Danube and the Vistula, which serve as essential routes for commercial freight barges, hydroelectric power generation and regional water supplies.
UK rainfall, Storm Austen and Storm Boelo
The United Kingdom was among several European nations struck by heavy rainfall and flooding during a stormy October. According to the Met Office, the country's national weather service, October was warmer, wetter and sunnier than average across the UK, with mean temperatures reaching 10.6°C (51°F), or 0.9°C (1.6°F) above normal.
Britain recorded 5.47 inches (138.9mm) of rainfall across the month, roughly 13 per cent above average, as Storm Austen and Storm Boelo crossed the country. On October 24, torrential rain produced the joint sixth-wettest day ever recorded across the UK.
During the storms, wind gusts exceeding 70mph battered exposed coastal areas, damaging buildings and forcing operators to cancel transport services. Several people died after falling trees, flooding and storm-related incidents hit parts of England, Scotland and Wales.
Thousands of homes lost electricity and major roads and railway lines suffered disruption during the severe weather. Rivers burst their banks in several areas following days of continuous downpours, triggering flood warnings and resident evacuations as emergency services responded to dozens of incidents.
UK winter storm warnings from climate scientists
Climate scientists warn that the recent deadly storms could mark the beginning of a turbulent winter driven by El Niño. Experts say the Pacific climate phenomenon threatens to bring fierce winds, torrential rain and snow across the UK over the coming months.
Researchers noted that the stormy autumn weather aligns with patterns typically seen during a strong El Niño year, and warned that an event among the strongest in living memory could severely disrupt Britain's winter weather.
Professor Ilan Kelman, a disaster and climate expert at University College London, told the Daily Mail: "The standard results from an El Niño for the UK are absolutely a warmer and stormier autumn, and then a colder and stormier winter. What El Niño does, it increases the likelihood that we will get more storms, and that they will be more intense."
