Britain to face ARCTIC WINTER as mild autumn triggers polar gales and heavy snow

Scientists have re-issued stark warnings ahead of what some have claimed is set to be the coldest winter for a century.

They said a lengthy spell of extreme and potentially devastating weather is just around the corner partly thanks to the unusually mild autumn.

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Looking at air flow in the upper atmosphere to produce an index called the October Pattern Index (OPI ) experts have said everything points towards a negative Arctic Oscillation this winter.

The resulting weak jet stream, which usually holds the cold at bay over the North Pole, will give way to a blast of freezing air which will sweep across the UK.

Experts expect this by the middle of November with snowstorms and numbing Arctic gales set to wreak havoc at airports and on the country’s transport systems.

The OPI was devised by Italian scientists Riccardo Valente and Professor Judah Cohen with this year’s readings dangerously similar to those taken during the catastrophic winter of 2009/10 - the coldest in 31 years.

The findings support recent claims that this winter could be one of the worst in decades.

James Madden, forecaster for Exacta Weather said: “We are reaching a stage where the final OPI value is currently at -2.43.

“Anything below -1.5 correlates highly with a blocked winter pattern of cold and snow for the UK.

“It appears to correlate well with a scenario similar to the winter of 2009/10 at the very least.

“In addition to this the Siberian snow cover is also well ahead of schedule and is another strong signal for a harsh winter based on previous studies for a negative Arctic Oscillation for the December to March period.

“The worst case and more plausible scenario could bring something on a similar par to the winter of 2009/10, the coldest in 31 years, or an event close to 2010/11 which experienced the coldest December in 100 years.”

Jim Dale, forecaster for British Weather Services, said the unusually mild autumn weather is an indicator of a harsh winter ahead.

He said the climate often follows a “balancing” pattern where periods of unusually warm or cold weather are followed by the direct opposite.

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He said: “We could see a sharp difference as the winter unfolds, this mild weather could bring a false sense of security.

“There is always another side to the coin and in the long run on the balance of probability we could see a very different picture.

“I am not sure about a record winter, but certainly things have a way of balancing out.”

Mr Madden warned to brace for a “shock to the system” with a “significant” snow event possible in weeks.

He said: “As we progress throughout November, it will begin to turn gradually cooler, in particular, within the second half of the month as blocking becomes a more prominent feature and the jet stream diverts further south.

“This will be due to expanding cold from the Arctic region, and this will also allow for the development of some much colder intrusions of air and snow for the UK.

“Some of the snow events are likely to be quite significant with blizzards across higher ground, and a number of potentially notable snow events are also possible across some lower levels within this period, in particular, in some exposed coastal areas to the north and west of the country.

“We are also likely to see the development of some widespread frosts and rather extensive fog patches across the country within this period, and this will come as quite a shock to what we have experienced throughout this autumn to date.

“However, some spikes of milder conditions may also develop within this period, in particular, in some parts to the south of the country, and these will be accompanied by some rather windy and quite stormy conditions at times.”