BBC Weather issues verdict on El Nino and polar vortex bringing major snow to UK

BBC Weather issues verdict on El Nino and polar vortex bringing major snow to UK Weather forecasters have warned that this year's super-strength El Nino could lead to extreme cold and snow across the UK due to the polar vortex weakening BBC Weather forecasters have explained whether we can expect extreme wintry conditions and major snowfall this winter due to El Nino. Experts have suggested this year’s El Nino, expected to be the strongest ever, could lead to the polar vortex collapsing. The polar vortex is a ring of strong westerly winds which surrounds the North Pole, and when it weakens - or collapses - it can have an impact on the jet stream. The Met Office has said El Nino could weaken the polar vortex over the coming months, potentially leading to a process known as sudden stratospheric warming. This causes cool air to rush downwards, changing the position of the jet stream and potentially causing a ‘blocking pattern’ that keeps cold conditions locked in place. Sudden stratospheric warming is what led to the infamous Beast from the East in 2018, during which 22 inches of snow fell in some parts of the UK. However, BBC Weather forecasters say there are no guarantees of extreme wintry weather this year. They explain that when the polar vortex wobbles, “it can deliver colder northerly or easterly winds which can bring the UK its coldest winter weather”. However, they add: "It does not always translate into changes in weather patterns at the Earth's surface. “Equally, periods of a meandering jet stream and cold winter weather often occur without significant changes in the polar vortex.” Moreover, even though El Nino can make it “more likely that the polar vortex becomes disrupted, increasing the chance of ice and snow”, the BBC says “the links are unclear and the evidence is mixed”. The so-called Big Freeze of 2009/10 was the coldest winter in three decades at the time and coincided with an El Nino, but so did the unseasonably warm winter of 2006/07. The BBC Weather forecasters conclude: “So while El Nino is already having big impacts on global weather, and may influence the polar vortex later in winter, snow and ice in the UK is far from guaranteed.”