The northern hemisphere has sweltered through its hottest summer yet, eclipsing a notorious benchmark as a huge El Nino looms over Australia.

Environment Secretary Dame Angela Eagle has urged people to store supplies in case of extreme weather events. An unprecedented El Nino event – when sea temperatures in tropical eastern Pacific rise 0.5C above the long-term average – is forecast to reach more than 3C in the coming months, making this year’s event “the largest since the 19th century”, according to the Met Office. El Nino creates a heightened risk of drought in the tropics, southern Africa and north-east Australia, while north-western Europe – including the UK – is likely to experience wetter and stormier conditions in the coming autumn and early winter, the forecaster said.

The US has sweltered through its hottest summer in 132 years of records, eclipsing the notorious Dust Bowl benchmark as a powerful El Niño strengthens across the Pacific.

Four of America’s five hottest summers have now occurred since 2021, as Australia gears up for a particularly hot one over Christmas.

During the most recent summer, average temperature across the mainland US reached 23.6C between June and August, according to the National Oceanic and Atmospheric Administration.

That was about 0.2C hotter than the previous record, shared by the devastating Dust Bowl summer of 1936.

August also became the country’s hottest on record, averaging 24.2C. The average daytime maximum reached 31.4C, another record, after July was separately declared the hottest month the contiguous US (excluding Alaska, Hawaii, and offshore US territories) had experienced since national measurements began in 1895.

“This is occurring exactly as forecast by scientists literally decades ago,” Texas A&M University climate scientist Andrew Dessler told AFP.

The US has sweltered through its hottest summer in 132 years of records, eclipsing the notorious Dust Bowl benchmark as a powerful El Niño strengthens across the Pacific. Credit: NOAA/NCEI.

August was the hottest on record. Credit: C3S/ECMWF.

“The interesting question is not whether we will keep breaking heat records (we will), but whether we’re going to do anything about it or just stand there while the climate train runs us over.”

This summer’s record was driven more heavily by unusually warm nights, which deprived people, buildings and infrastructure of the usual chance to cool down.

“We’ve eclipsed the summer of the Dust Bowl drought of 1936, but just by a hair, it’s like a photo finish,” NOAA monitoring chief Karin Gleason said.

She said the warmer atmosphere can retain more moisture, helping trap heat overnight.

The heat was accompanied by expanding drought. By September 1, 59.1 per cent of the contiguous US was in drought — an increase of more than 10 percentage points in a month. Texas and Oklahoma received less than 30 per cent of their normal August rainfall.

“The record summer is certainly in line with what we expect from human-caused climate change; as the US and the planet as a whole warms, heatwaves become both more frequent and more intense,” Berkeley Earth climate scientist Zeke Hausfather said.

“It should absolutely send alarm bells ringing, as these hotter summers lead to increased heat stress, higher energy demand for cooling, and strain on infrastructure and public health systems.”

Satellite image shows Hurricane Lowell (L), Hurricane Karina (C), and a Hurricane Marie (R) over the Pacific Ocean on September 4, 2026. Credit: Handout / NOAA / AFP

What it means for the Aussie summer

Australia has warmed by an average of 1.51C since national records began in 1910, according to the CSIRO and Bureau of Meteorology. Eight of Australia’s nine warmest years on record have occurred since 2013.

The nation’s hottest summer remains 2018-19, when the average temperature was 2.14C above the 1961-90 average. That demolished the previous record by 0.86C and helped produce widespread heatwaves, drought and dangerous fire weather.

The Bureau says a strong El Niño is now established and likely to become a very strong event in late spring or summer. Its latest outlook favours above-average daytime temperatures across most of Australia south of the tropics, warmer nights across most of the country and below-average spring rainfall in parts of the south and east.

An increased bushfire risk has been forecast for parts of every state and much of the Northern Territory.

El Niño typically pushes rainfall away from eastern and central Australia while lifting temperatures, but it is not a weather remote control. The Bureau cautions that even a very strong event does not guarantee equally strong Australian impacts, with the Indian Ocean and unusually warm seas around Australia also influencing rainfall and storms.

The World Meteorological Organisation says there is a near-100 per cent probability that El Niño will persist through February 2027.

Globally, 2026 currently ranks as the second-hottest year on record through August, behind 2024. But August was the joint-hottest month ever measured worldwide, and the strengthening El Niño means 2026 could yet challenge the annual record. Scientists broadly expect its largest temperature impact to arrive in 2027.

“The flip side of that is that we can prevent this from getting worse,” University of Pennsylvania climatologist Michael Mann said.

“The consensus among climate scientists is that surface warming of the planet will stop when we reach zero carbon emissions, and we have the clean energy technology to do this. It’s simply a matter of finding the political will.”

Home

‘Alarm bells ringing’: US summer heat shatters record, EU records hottest August on record