Record El Niño threatens UK with stormy autumn, uncertain winter ahead

Thousands of miles away in the Pacific Ocean, a weather system is gathering strength that will reshape the autumn sky above Britain. This year's El Niño is shaping up to be the most powerful in living memory, and the Met Office is already tracking its fingerprints across the globe—including here, where it promises to deliver a wet and stormy season ahead.

El Niño develops when warm water spreads across the tropical Pacific, disrupting wind patterns that normally steer weather systems around the planet. The immediate casualties are elsewhere: Peru and Ecuador face heightened flooding and landslides, while Australia braces for drought and wildfire. But the atmosphere does not respect distance. The ripples spread outward, and the UK sits squarely in their path.

Professor Adam Scaife, who leads long-range forecasting at the Met Office, has been studying weather patterns for decades. He says he has never seen anything quite like what is developing now. The scale is unprecedented in modern climate records. As this El Niño peaks toward the end of 2026, its influence will intensify, and the signals are already visible in the forecasts. Autumn rainfall and storminess are likely to increase, particularly as November and December arrive. The storms will bring strong winds capable of toppling trees, disrupting transport, and cutting power to homes and businesses.

There is a peculiar irony in the timing. Britain has endured a summer that appears destined to be the hottest on record, with drought conditions persisting across large swathes of the country. A wet autumn would ordinarily sound like relief. But climate change has altered the equation. The warming atmosphere is making intense rainfall more probable, and when those storms arrive, they will carry a heightened risk of flooding. The winter of 2015 and 2016 offers a cautionary reference point: that period coincided with a very strong El Niño and brought successive major storms that experts at the time called the most extreme flooding on record.

What happens in winter remains murkier. El Niño can occasionally trigger cold spells in late winter, but the connection is weak and the historical record is mixed. The Big Freeze of 2009 and 2010, the coldest winter in three decades, did coincide with an El Niño. Yet the winter of 2006 and 2007 was also an El Niño year, and it turned out unseasonably warm. The further forecasters peer into the future, the more uncertainty clouds the picture. A cold spell in early 2027 is possible but far from certain.

Next summer's prospects are equally uncertain, though the global picture is clearer. A very strong El Niño typically raises worldwide average temperatures by about 0.2 degrees Celsius. That modest figure sits atop the warming already driven by human-induced climate change, multiplying the risk of heatwaves across the world. But El Niño's effects are not uniform. Its connection to hot weather specifically in the UK remains unclear. Dr Akshay Deoras, a climate scientist at the University of Reading, notes that long-term global warming remains the dominant force shaping Britain's rising temperatures and increasing risk of extreme heat. Whether the additional warmth from El Niño will tip next summer toward exceptional heat remains too early to say, though the combination of El Niño's warming and the UK's already warmer climate could create the conditions for it.

No two El Niños behave identically. This one may increase the odds of certain weather patterns, but it guarantees nothing. What is certain is that the system is already in motion, and autumn will arrive with it.