Polar vortex is getting stronger — what does it mean for winter in the UK

Britain’s winter could be in for a dramatic change as El Niño grows

El Niño is currently one of the biggest talking points. The Pacific warming event can influence weather across the globe, and there have been growing expectations that this year's event could be unusually strong. 

Ocean temperatures in affected areas could end up around 1.5C to 2C higher than normal.

For the UK, one possible outcome is a mild but unsettled autumn, followed by a colder and stormier winter. The Met Office has previously linked El Niño later in the season with a higher chance of cold snaps.

Prof Ilan Kelman, from University College London, said the pattern could also contribute to a hotter summer next year. 

He warned that the UK needs to be better prepared for increasingly difficult weather conditions as climate change continues to intensify heatwaves.

Polar vortex forecasts are raising questions about Britain’s winter

There is also growing interest in what happens above the Arctic. The polar vortex, a band of strong winds surrounding the North Pole during winter, is currently showing stronger signals than usual for September.

That is not necessarily bad news for Britain. A strong vortex helps keep the Arctic's coldest air contained. If it becomes significantly weaker, pockets of freezing air can push further south.

Some longer-range forecasts currently point towards a possible weakening in January or February 2027. 

However, Dr Akshay Deoras of the National Centre for Atmospheric Science stressed that there is not enough information yet to know whether the polar vortex will have a major effect on Britain's winter weather.

For now, both patterns are being monitored, but neither provides a reliable picture of exactly what the UK will experience months from now.