August 2026 at 16.96 degrees: the hottest month ever measured, tied with July 2023
The Copernicus bulletin of September 10 records a global average of 16.96 °C, 0.85 above the 1991-2020 average and 1.65 above the estimated preindustrial level. Extra-polar oceans hit a record for the month, at 21.07 °C.
Friday, 11 September 2026
The monthly climate bulletin of the Copernicus Climate Change Service, published on September 10, 2026, assigns August 2026 a global average surface air temperature of 16.96 °C. It is the highest value in the ERA5 dataset, which starts in 1940, and it equals July 2023.
The unit and the scale. An absolute global temperature value says almost nothing unless anchored to a reference. The bulletin uses two: the average of the 1991-2020 thirty-year period, against which August 2026 is warmer by 0.85 °C, and the estimated preindustrial level for the 1850-1900 period, against which the difference is 1.65 °C. The latter is the reference used to measure the 1.5 °C threshold used in climate agreements: August 2026 is the first month to exceed it since November 2025.
| Indicator, August 2026 | Value |
|---|---|
| Global average surface air | 16.96 °C |
| Deviation from 1991-2020 average | +0.85 °C |
| Deviation from 1850-1900 (estimate) | +1.65 °C |
| Extra-polar oceans (60°S-60°N) | 21.07 °C |
| Europe, land surface | 20.26 °C |
The ocean. The average surface temperature of extra-polar oceans, in the band between 60° south latitude and 60° north, reached 21.07 °C: a record value for the month of August, above the 20.98 °C of 2023. On August 24 and 25 the daily maximum of 21.11 °C was reached. The difference between the two monthly records is nine hundredths of a degree — a small amount in absolute terms, considerable over a surface that covers most of the planet and that stores heat much longer than the atmosphere.
The ice. The two extremes give signals of different intensity: Arctic sea ice extent was the twelfth lowest ever recorded for the month, Antarctic sea ice extent the fourth lowest. Neither value is a record; both are in the low end of the series.
Europe. Over the continent’s land surface, the August average was 20.26 °C, the fourth-warmest August in the series. The record instead concerns the entire season: summer 2026 was the warmest ever recorded in western Europe, surpassing the previous record of 2003.
“August 2026 was a remarkable month in the global climate record” (transl. from English) — Samantha Burgess, Strategic Lead for Climate, ECMWF
The limits of the data. ERA5 is not a network of thermometers but a reanalysis: it combines observations and models to reconstruct a homogeneous series starting in 1940, so “ever recorded” comparisons hold within that series, not for the entire history of climate. The 1850-1900 level is an estimate, as the bulletin itself indicates by speaking of an estimated preindustrial level: the comparison with the 1.5 °C threshold inherits its uncertainty. A single month above 1.5 °C, moreover, is not equivalent to the long-term breach referred to in climate agreements, which is measured over multi-year averages.
The same figures are reported by Euronews, based on a report by the AFP agency, and by The Watchers. The next verifiable comparison is the September bulletin, which will measure whether the return above 1.5 °C lasts more than one month.