El Niño set to be ‘strongest in living memory’, says UK’s Met Office

The UK's Met Office warns that an El Niño event developing in the Pacific Ocean is likely to be the strongest in living memory, potentially making 2027 the hottest year on record. This powerful climate phenomenon raises global temperatures and can heighten the risks of extreme weather, particularly with human-induced climate change already in play. As a result, the Met Office anticipates the UK could face a wetter, stormier autumn.

El Niño, which occurs roughly every two to seven years and lasts approximately a year, occurs when trade winds weaken or reverse, allowing warm water to migrate eastward. This releases heat into the atmosphere, raising global temperatures and altering rainfall patterns. Currently, sea surface temperatures in a key Pacific area are more than 2C above average, and forecasts suggest they could exceed 3C, making this event unparalleled in records dating back to 1950.

The Met Office's head of long-range forecasting, Prof Adam Scaife, describes this El Niño as "unprecedented," noting he has never seen a signal this intense in their forecasts. If the temperature anomalies continue to grow, it's possible this could be the strongest El Niño in 500 or even 1,000 years, according to climate scientist Dr Zeke Hausfather from Berkeley Earth. However, attributing such events to such vast historical scales is challenging.

The changes in heat distribution and wind patterns associated with El Niño can yield varied impacts on the global weather. In the current year, suppressed monsoon rains in India and reduced hurricane activity in the Atlantic are being observed. For the UK, El Niño could increase the likelihood of wet, stormy conditions during autumn and early winter and potentially bring cold weather late in the winter, though these links are not definite.

While El Niño is not currently considered a major driver of the recent record-breaking heatwaves, it may significantly influence the UK's weather in the autumn and early winter.