Ice cold chill to return driven by ‘disturbances across the globe’

Fears of a major Beast from the East snow deluge have in the past week eased with forecasters issuing fresh alerts for wind and rain through the rest of this month.

The culprit is a ferocious jet stream charging out of the Atlantic steering volatile low-pressure systems into Britain.

However, the jet is about to get a nudge from the knock-on effect of thunderstorms building over the Indian and western Pacific Oceans – the so-called Madden-Julian Oscillation (MJO).

As with the better-known El Niño and La Niña events which happen off the coast of South America, the MJO can affect weather patterns thousands of miles away.

It can trigger waves in the jet stream – amplifications which affect weather systems coming into the UK from the Atlantic, sometimes turning it colder and drier.

Met Office meteorologist Aidan McGivern said: “There is something that’s happening in the Pacific.

“An enhanced area of ​​thunderstorms is affecting the western Pacific, and this is called the Madden-Julian Oscillation.

“When we get this enhanced activity, it can reverberate some energy and disrupt the jet stream and affect the jet stream that is coming in from the Atlantic.

“It means there are some hints that our jet stream may become a bit more amplified in a week or two.”

This would mean a colder, drier snap towards the end of the month and into the beginning of February, he added.

He said: “Although we are likely to see westerlies through the rest of January, higher pressure is perhaps more likely later.

“It means something a little less unsettled is favored beyond 10 days.”

While the exact effect of the MJO on the UK is debated, forecasters agree Britain’s weather through the coming weeks will be largely dominated by the jet stream and unsettled Atlantic weather patterns.

This will be bolstered by a strengthening Polar vortex causing the pool of air over the North Pole to shrink northwards to power the jet stream.

Mr McGivern said: “When the ring of strong winds across the Polar vortex is strong, it strengthens the jet stream coming in from the west, and that means westerlies are more likely than easterlies or northerlies.

“All the suggestions are that it will stay strong for the next few weeks, meaning westerlies are more likely than easterlies through the rest of January.”

Independent forecasters agree the outlook for the next month at least is one of rain, wind and largely milder temperatures.

While snow is not off the table, the overall theme throughout the rest of January is wet and unsettled.

Jim Dale, meteorologist for British Weather Services, said: “We are going to continue with the theme of a conveyor belt of unsettled weather conditions coming into Britain on the jet stream.

“This means more wind and more rain and the potential for flooding in parts of the country that have already seen heavy rainfall over the past fortnight.

“The jet stream will remain largely in control over the coming weeks, and I would not be surprised to see a named storm at some point, which would be the first of the season.”

But while the outlook is leaning towards mild and unsettled, the threat of the beast has not completely disappeared, added Mr Dale, an expert in weather safety and impacts.

He said: “There is the possibility for some changes to this pattern, especially as we go into February, and there will be colder spells in the mix as we go through the next few weeks.

“I would expect to see some of the cold coming back at some point before the end of winter, but this is likely to be more sporadic and shorter lived, rather than anything sustained.”

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