The La Niña phenomenon - a prolonged period of cooler temperatures in the Pacific Ocean - has prompted growing speculation the UK will face a long and freezing winter and “the coldest February for several years”.
Such reports were largely driven by memories of the last La Niña event in 2010 and 2011, where global temperatures hit record lows, causing serious snows in the UK and droughts in Africa.
The Met Office says the hallmarks of another La Niña, which means “The Girl” and is the counterpart to the Pacific warming phenomenon El Niño (The Boy), are now developing.
Some organisations have already declared a La Niña, but it is not yet universally agreed as definitions vary, though most include at least half a year of below-average sea surface temperatures.
However the Met Office told The Independent that warnings of a repeat 2010’s La Niña-driven freeze were premature as on existing evidence it looks like this year’s event will be much weaker.
Met Office spokesperson Grahame Madge said: “In 2010 we had a deep La Niña which sent a strong meteorological signal, and it was reflected in the weather in the UK with the cold weather we saw at the time.”
“At the minute, La Niña is just one of the global climate influences that affect our weather, but because it’s a weak signal it’s not going to dominate all the other influences on the UK climate.”
This likely means more drizzle, and fewer snow drifts, over Christmas with the current chill, which hit -5.3C (42F) in parts of Oxfordshire this week, expected to pass in the next few days.
But Mr Madge did say the system responsible for the current chilly conditions is characteristic of a La Niña-type system.
“The high pressure sat well to the west of the British Isles has been drawing in northerly air from much further north and that’s solely responsible for bringing in the cold conditions," he said.
“That’s exactly the sort of feature we would expect to see develop with La Niña conditions, whether that’s set to influence the rest of December remains to be seen.”
“We anticipate it will be colder than average, but it could just be half a degree it doesn’t mean six foot of snow.”
