October 2026 is on track to be the hottest October ever recorded — and 2027 could be even warmer

October 2026 is almost certainly going to be the hottest October ever recorded. That is the conclusion of climate scientists Andrew Dessler and Zeke Hausfather, who project that global temperatures this month will finish at around 1.76 degrees Celsius above pre-industrial levels, beating the previous October record of 1.7 degrees set in 2023. Their projection, reported by Scientific American on 30 October 2026, is based on data from the European Union’s Copernicus Climate Change Service.

At a glance

What happened: Climate scientists Andrew Dessler and Zeke Hausfather project, from Copernicus Climate Change Service data, that October 2026 will finish at around 1.76 degrees Celsius above pre-industrial levels — the hottest October ever recorded, beating the 1.7 degrees of October 2023. Scientific American reported the projection on 30 October 2026.

Why it matters: The record caps a year of broken records, including the United States’ hottest September, hottest first eight months and hottest 12-month period ever recorded, and the hottest global ocean temperatures ever recorded. September 2026 was already the second-warmest September on record at 1.63 degrees above pre-industrial levels, the second month in a row above 1.5 degrees.

What happens next: The heat is being amplified by a strengthening El Niño in the Pacific, which the World Meteorological Organization expects to peak in December and persist until February 2027. Scientists warn that 2026 is on track to be among the hottest years ever recorded, and that 2027 could be hotter still. The official Copernicus figure for October will be published in early November and may differ slightly from the projection.

If the projection holds, it will be the latest in a long run of broken records — and it carries a warning about what comes next. The heat is being driven by a “super” El Niño building in the Pacific Ocean, and Hausfather expects a run of record-setting months to follow, “culminating in a record-setting 2027”. Britain’s Met Office has already said that 2027 is very likely to replace 2024 as the warmest year on record.

This is not just a number on a chart. A hotter October means hotter seas, heavier downpours in some places and deeper droughts in others, and more pressure on the crops, water supplies and power grids that people depend on — including in Pakistan, where the 2026 monsoon already fell far short of normal.

The number that broke the record

The headline figure is 1.76 degrees Celsius, or about 3.17 degrees Fahrenheit, above pre-industrial levels. “Pre-industrial” means the average for 1850 to 1900, the period scientists use as a baseline for the world before large-scale burning of fossil fuels. October 2023, also an El Niño year, reached 1.7 degrees above that baseline, according to Dessler and Hausfather’s analysis. October 2026 is projected to beat it by about 0.06 degrees.

That may sound small. In the climate of a whole planet, it is not. Global monthly temperatures are averages over the entire surface of the Earth — land and ocean, tropics and poles — and they move slowly. A new record by six hundredths of a degree, on top of a record set only three years ago, means the whole system has shifted warmer. It also means the previous record did not stand for long: 2023 was the hottest year ever recorded at the time, and it was surpassed by 2024. The year 2025 was the third-hottest year ever recorded. Copernicus puts 2024 at 1.60 degrees above the 1850–1900 average, 2023 at 1.48 degrees and 2025 at 1.47 degrees.

The October projection is not yet the official figure. It is based on partial-month Copernicus data, and the official value will be published in the Copernicus monthly bulletin in early November. It may differ slightly. But Dessler and Hausfather describe the outcome as almost certain, and the margin is large enough that a small revision would not change the ranking. The month is, in their words, on track to be the hottest October ever recorded.

September set the stage

October did not come out of nowhere. September 2026 had already been exceptionally warm. The Copernicus Climate Change Service reported on 9 October 2026 that September was the second-warmest September ever recorded, with a global average surface air temperature of 16.27 degrees Celsius — 0.82 degrees above the 1991–2020 average and 1.63 degrees above the pre-industrial baseline. Only September 2023 was warmer, by just 0.11 degrees.

September was also the second consecutive month in 2026 with global temperatures above 1.5 degrees, continuing a run that began in August 2026. It was the first time since November 2025 that two months in a row had passed that mark. The oceans were warm too: the average sea surface temperature between 60 degrees south and 60 degrees north reached 21.05 degrees Celsius, the highest ever recorded for September.

Looking at the year so far, Copernicus said that the first nine months of 2026 made it the second-warmest year on record at that point, behind only 2024 and ahead of 2023 and 2025.

Europe felt the heat directly. Western Europe had its joint-warmest September, tied with 2023, following its hottest summer ever recorded.

The engine behind the heat: a super El Niño

The immediate driver of the record is El Niño, the natural climate pattern that occurs when part of the Pacific Ocean becomes unusually warm, changing weather around the world. El Niño does not create heat from nothing: it releases heat that the ocean has already stored. But when it arrives on top of a planet already warmed by greenhouse gases, it pushes global temperatures to new highs.

This El Niño is unusually strong. The World Meteorological Organization announced on 8 October 2026 that the phenomenon would intensify in the coming months, could peak in December, and could persist until February 2027. The agency estimated that the current episode could be one of the most intense recorded since 1950. Sea surface temperatures in the equatorial Pacific rose from 1.6 degrees above average in June 2026 to 2.5 degrees in August, and for the October-to-December period the figure is forecast to reach about 3.7 degrees, exceeding the previous record of 2.6 degrees set between November 2015 and January 2016. The WMO put the probability that El Niño will persist until February 2027 at close to 100 per cent.

The United States National Oceanic and Atmospheric Administration, known as NOAA, gives an 83 per cent chance that October to December will be a historically strong El Niño, stronger than any since reliable records began in 1950.

That matters because of timing. In past El Niños, the record for the hottest year on Earth fell the year after the peak — in 1998 after the 1997 peak, in 2016 after the 2015 peak, and in 2024 after the 2023 peak. The reason is that the heat El Niño releases from the ocean takes two to three months to show up fully in global surface temperatures. With this event expected to peak in November or December 2026, its biggest effect on the annual record is likely to land in 2027.

Hausfather put it plainly: “This year’s record-setting October is a sign that the ‘Super El Niño’ is kicking into gear and will likely be the first in a series of record-setting months, culminating in a record-setting 2027.” The Met Office agrees, saying 2027 is very likely to replace 2024 as the warmest year on record. Berkeley Earth, an independent research group, estimated in September 2026 that there was a 93 per cent chance 2026 itself would become the hottest year on record.

What 1.5 degrees does and does not mean

Much of the reporting around these records mentions 1.5 degrees Celsius. That number comes from the 2015 Paris Agreement, under which countries committed to pursuing efforts to limit global warming to 1.5 degrees above pre-industrial levels. It is important to understand what passing it does and does not mean.

A single month, or even a single year, above 1.5 degrees does not mean the Paris goal has been permanently broken. The goal is measured over a long period — roughly 20 years — not month by month. The fact that September and October 2026 both passed 1.5 degrees, and that the 12 months to September 2026 averaged exactly 1.50 degrees above pre-industrial levels, does not by itself breach the agreement.

What it does show is how close the world now sits to that limit, and how often it crosses it. The world has already had single years above 1.5 degrees in the Copernicus data, and the three-year stretch from 2023 to 2025 was the first to average above 1.5 degrees. Buontempo has warned that crossing the Paris Agreement’s long-term limit is now only a matter of time, and that the question is how far the world overshoots it and for how long. “Every tenth of a degree matters,” he said in October 2026.

The long-term driver is the burning of fossil fuels, which has pushed greenhouse gas levels to record highs. El Niño is a short-term amplifier on top of that long-term warming. When it fades, temperatures will fall back somewhat — but to a higher level than after previous El Niños, because the underlying warming has continued.

The United States had a record year too

The heat has not been spread evenly, and the United States has had a particularly hot year. October’s likely global record follows what Scientific American describes as several other superlative moments so far in 2026, including the country’s hottest September, hottest first eight months and hottest 12-month period ever recorded, as well as the hottest global ocean temperatures ever recorded.

A hotter ocean matters for everyone. Warm seas fuel stronger storms, hold more moisture that falls as heavier rain, and damage coral reefs and fisheries. The record ocean temperatures of 2026 are part of the reason the Atlantic hurricane season and the Pacific typhoon season have been so closely watched this year.

What it means for Pakistan

Pakistan has felt the heat in its own way. The 2026 summer monsoon finished 19 per cent short of normal for the country as a whole, and 51 per cent short in Sindh, according to the Pakistan Meteorological Department. Water stored in the country’s reservoirs started the dry season 6 per cent below the average of the past decade.

El Niño years have a mixed record for Pakistan. They can shift the winter rains that water the wheat crop, and they often bring warmer-than-normal temperatures. The PMD’s own outlook for the first week of November shows the country staying dry, with Karachi forecast at 35 to 37 degrees Celsius — hot for November — while the north gets its first snow. The final outcome for Pakistan’s winter will depend on how the El Niño develops over the next two months, and on whether the winter westerly systems that bring rain to the north and west arrive on time.

What is certain is that a warmer world raises the stakes for Pakistan. The country is already one of the most exposed to climate extremes, from the floods of 2022 to the heatwaves that strike Sindh and Punjab each summer. Each fraction of a degree of global warming adds to the heat that Pakistani cities, farms and power grids must cope with.

Frequently asked questions

Is October 2026 officially the hottest October on record?

Not yet, officially. The figure of around 1.76 degrees Celsius above pre-industrial levels is a projection by climate scientists Andrew Dessler and Zeke Hausfather, based on Copernicus Climate Change Service data, reported on 30 October 2026. The official Copernicus monthly bulletin will be published in early November and may differ slightly, but the scientists describe the record as almost certain.

What was the previous hottest October?

October 2023, which reached 1.7 degrees Celsius above pre-industrial levels, according to Dessler and Hausfather’s analysis. October 2026 is projected to beat it by about 0.06 degrees.

Why is 2026 so hot?

Two forces are working together. The long-term cause is human-caused climate change from burning fossil fuels, which has pushed greenhouse gas levels to record highs. The short-term cause is a very strong El Niño in the Pacific, which releases heat stored in the ocean and pushes global temperatures higher. The World Meteorological Organization expects this El Niño to peak in December 2026 and last until February 2027.

Will 2027 be hotter than 2026?

That is what the scientists expect. In past El Niños, the hottest year on record fell the year after the peak. The Met Office says 2027 is very likely to replace 2024 as the warmest year on record, and Zeke Hausfather expects a run of record-setting months culminating in a record-setting 2027.

Does two months above 1.5 degrees mean the Paris Agreement has failed?

No. The Paris goal of limiting warming to 1.5 degrees is measured over a long period, roughly 20 years, not month by month. Single months and single years above 1.5 degrees do not breach it. But the repeated crossings show how close the world is to that limit, and the Copernicus Climate Change Service says the run of months above 1.5 degrees is likely to last into 2027.

How is the global temperature measured?

The figures come from datasets such as Copernicus’s ERA5, which combines observations from weather stations, satellites, ships, aircraft and buoys around the world into a single picture of the planet’s surface air temperature. The “anomaly” is the difference between the measured temperature and the average for a reference period — in this case, the pre-industrial period of 1850 to 1900.

Conclusion

October 2026 will almost certainly go down as the hottest October ever measured, at around 1.76 degrees Celsius above pre-industrial levels. It follows the second-warmest September on record, the warmest September oceans on record, and a year of broken heat records in the United States and around the world.

The record is not a one-off. It is the product of a long-term warming trend and a powerful El Niño that is still building toward its peak in December. If the pattern of past El Niños holds, the hottest months are still ahead, and 2027 is likely to be the warmest year ever recorded.

That is not a prediction of doom, but it is a warning with a deadline. Every tenth of a degree matters — for the heat in Karachi and Lahore, for the water in Pakistan’s reservoirs, and for the farmers waiting on winter rain. The official Copernicus figure for October will confirm the record in early November. The trend behind it has been confirmed for years.

This article is for general information and education only. It is not legal or financial advice.

Sources

• Scientific American, “This October is on track to be the hottest ever recorded”, 30 October 2026 — https://www.scientificamerican.com/article/this-october-is-on-track-to-be-the-hottest-ever-recorded/
• Copernicus Climate Change Service, “Copernicus: Second warmest September as global temperatures stay above 1.5°C”, 9 October 2026 — https://climate.copernicus.eu/copernicus-second-warmest-september-global-temperatures-stay-above-15degc
• Copernicus Climate Change Service, “Surface air temperature for September 2026” — http://climate.copernicus.eu/surface-air-temperature-september-2026
• World Meteorological Organization announcement on El Niño intensifying through December, reported 8 October 2026 — https://informat.ro/en/environment/el-nino-intensifies-and-could-become-the-strongest-on-record-142504
• IIPMaps, “Hottest year on record 2026: global climate data and India” — https://iipmaps.com/blog/hottest-year-record-2026-global-climate/