August 2026 was the joint warmest month ever recorded, tied with July 2023. Last month also saw the average sea surface temperature (SST) over the extra-polar ocean reach a record high, due to global heating from burning fossil fuels and rapidly increasing SSTs in the equatorial Pacific associated with strong El Niño conditions – as reported by the Copernicus Climate Change Service (C3S), implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF).

Global-average surface air temperature (°C) for 2023 (orange), 2024 (yellow), and 2026 (dark red). All other years between 1940 and 2025 are shown with grey lines. Data source: ERA5. Credit: C3S/ECMWF.

With a global average surface air temperature 1.65°C higher than the estimated pre-industrial baseline, this August was the first month to exceed 1.5°C since November 2025. The month saw the joint highest monthly average SST ever recorded across the extra-polar ocean*, tied with March 2024, and the highest daily global SST over the extra-polar ocean ever recorded, at 21.11ºC. Meanwhile, record high SSTs were seen across the tropical Pacific, an area where a potentially extreme El Niño event continues to intensify. The impacts of this event are already being felt over land, with conditions favouring the intensification of seasonal wildfires across Indonesia, as reported by the Copernicus Atmosphere Monitoring Service (CAMS).

Anomalies and extremes in sea surface temperature for August 2026. Colour categories refer to the percentiles of the temperature distributions for the 1991–2020 reference period. The extreme (“coolest” and “warmest”) categories are based on August rankings for the period 1979–2026. Values are calculated only for the ice-free oceans. Areas covered with sea ice and ice shelves in August 2026 are shown in light grey. The map outlines the Niño 3.4 region used to monitor El Niño conditions. Data source: ERA5. Credit: C3S/ECMWF.

The month marked the end of western Europe’s warmest summer on record, surpassing the previous record set in 2003. The region also saw further heatwaves in August, continuing an exceptional run of extreme heat that began in May. Much of the region and large parts of central and eastern Europe also saw widespread dryness in August, in some cases persisting since May, with severe drought conditions reported in France, the UK, Hungary, Romania and Serbia. Across the dry regions, major European river flows were exceptionally low, including – from west to east – the Rhine, Danube, Southern Bug and Dnieper experiencing exceptionally low flows.**

(Left) Anomalies and extremes in surface air temperature in June–August 2026. Colour categories refer to the percentiles of the temperature distributions for the 1991–2020 reference period. The “coolest” and “warmest” categories identify areas where temperatures were the lowest or highest for June–August during 1979–2026. (Right) Average June–August surface air temperature anomalies for western Europe (11°W–15°E, 37°–55°N). Anomalies are relative to the June–August average for the 1991-2020 period. Data source: ERA5. Credit: C3S/ECMWF.

Samantha Burgess, Strategic Lead for Climate at ECMWF, commented:

“August 2026 was a remarkable month in the global climate record. It was both the warmest August and the warmest month ever recorded, with global temperatures reaching 1.65°C above pre-industrial levels, marking the return of global temperatures above 1.5°C. Combined with record global sea surface temperatures and the warmest summer on record for Western Europe, these observations show how climate change is driving extremes across both the atmosphere and the oceans. The impacts of these conditions are increasingly being felt by communities, economies and ecosystems across the world.”

August 2026 – Surface air temperature and sea surface temperatures highlights

Global surface air temperature

• The global-average surface air temperature in August 2026 was 16.96°C, 0.85°C above the 1991–2020 average, making it the warmest August globally in the ERA5 dataset, surpassing the previous joint record set in 2023 and 2024.
• August 2026 was also the joint-warmest month ever recorded globally across all calendar months, on par with July 2023.
• August 2026 was 1.65°C above the estimated pre-industrial 1850-1900 average, marking the first month above 1.5°C since November 2025.
• The period from June to August 2026 was the joint-warmest on record globally, on par with 2024.

Europe surface air temperature

• The average temperature over European land in August 2026 was 20.26°C, 1.10°C above the 1991-2020 average for the month, making it the fourth-warmest August on record.
• Summer 2026 (June to August) was the third warmest on record for Europe, behind 2024 and 2022.
• Western Europe experienced its warmest summer on record, surpassing the long-standing 2003 record. The 2026 season was marked by a succession of exceptionally early, persistent and intense heatwaves across the region.

Sea surface temperatures (SSTs)

• The average SST for extra-polar oceans (60°S–60°N) in August 2026 was the higheston record for the month, at 21.07°C, surpassing the previous August record of 20.98°C set in 2023.
• The average extra-polar SST for August 2026 was also the joint highest on record across all calendar months, on par with March 2024.
• SSTs remained exceptionally high across much of the tropical Pacific, where El Niño conditions are present and forecast to further strengthen in the coming months, potentially into one of the strongest El Niño events on record.
• Around Europe, SSTs reached record highs for August along the Atlantic coast and in the western Mediterranean, associated with widespread strong or severe marine heatwave conditions.

August 2026 – Hydrological variables highlights

Europe

Drier-than-average conditions in Europe

• In August 2026, parts of western Europe and large regions of central and eastern Europe were drier than average. 
• The August precipitation deficit in western Europe was less severe than earlier in the season, and more pronounced in the east and southeast, coinciding with widespread heatwave conditions. 
• Surface soils nevertheless showed exceptionally low levels of moisture throughout the dry areas, reflecting the legacy of the previous months.   
• The dry conditions were led to widespread drought and wildfire activity across several regions of the continent, as widely reported.
• River flows were largely below average across the dry regions, with conditions worsening in central and eastern Europe compared with July. The Danube, Rhine, Southern Bug and Dnieper saw exceptionally low flows, while the Vistula, Glomma, Rhône, Seine and Po also reached exceptionally low levels before recovering slightly following late-August rainfall.

Wetter-than-average conditions in Europe

• Wetter-than-average conditions occurred in western Iberia, the Alpine region, northeastern Europe, eastern Türkiye and adjacent regions, with heavy rainfall causing local flooding in several areas.

European summer

• In summer 2026, conditions were much drier than average in western and central Europe, southern Scandinavia and southeastern Europe. The precipitation deficit, more pronounced over the western regions in June, progressively shifted eastward during the season. 
• Severe impacts of these conditions included widely reported exceptional drought and wildfire activity and related emissions. 


• In contrast, western Iberia, southern Greece, southern Türkiye and Cyprus, as well as northeastern Europe, were wetter than average.
• For the season as a whole, much of continental Europe saw lower than average river flow. Large stretches of the Seine, Rhône, Loire and Glomma recorded their lowest seasonal flows since the beginning of the data record in 1992, with record-low conditions extending along the entire length of the Danube, Vistula and Rhine.

Other regions outside the tropics 

• Much of the southern USA and northern Mexico, parts of Canada, the Maghreb, part of the Horn of Africa, Siberia, large parts of central Asia, China, South America, South Africa, and northern Australia were drier than average.
• Wetter-than-average regions in August 2026 included the eastern USA and Canada, Alaska, parts of western and eastern Russia, the northern part of the Indian subcontinent, Chile and southeastern Brazil as well as easternmost Asia, including eastern China, Taiwan and Japan.

Boreal summer

• In the period from June to August 2026, the central and eastern USA and northern Canada, northern Siberia and part of central Asia, the Maghreb, the Horn of Africa, much of Brazil, Madagascar and much of northern Australia were drier than average.
• Wetter-than-average regions included the southwestern USA, central Canada, Alaska, western Russia, easternmost Asia, part of central Asia and southern regions of Australia.

August 2026 – Sea ice highlights

• In August 2026, Arctic sea ice extent ranked 12th lowest for the month, with particularly low sea ice cover north of Franz Josef Land and Severnaya Zemlya, in the Russian Arctic sector.
• By the end of August, as the daily Arctic sea ice extent approached its annual minimum, expected in September, it ranked 13th lowest for that time of year.
• Antarctic sea ice extent ranked fourth lowest for August, with below-average sea ice cover most pronounced in the Amundsen Sea and Indian Ocean sector.

Footnotes

* This finding is based on data from the ERA5 dataset. The monthly average SSTs were not the highest on record according to some other datasets.

** More analysis on Europe’s extreme summer will be published at the end of the month.