Polar vortex 2023: Met Office UK forecast for February - what is a polar vortex and sudden stratospheric warming?

Depending on who you ask, it could get even colder in February

February in the UK could turn out to be rather chilly (to put it mildly), with Brits being warned about a "polar vortex" that could emerge from the North Pole, according to some forecasters.

However, not everyone is convinced, and other weather watchers say a significantly cold snap for the month is unlikely.

The Met Office had predicted that this week may have seen a sharp decline in high-altitude polar vortex winds, which loop around the North Pole and trap chilly air in the Arctic.

Normally restricted to the Arctic, polar vortex winds have been visiting lower latitudes more frequently and staying longer than expected in recent years.

New maps and models show that this may not be the case. So what can we expect from February’s temperatures? Here is everything you need to know.

What is a polar vortex?

Simply put, a polar vortex is a mass of extremely cold air that is located above the North and South Poles of the planet.

A huge area of low pressure, which revolves anticlockwise at the North Pole and clockwise at the South Pole, governs this chilly, dense air, keeping it localised over the Arctic region - most of the time.

What causes polar vortex conditions over Europe?

A member of the public makes their way through the snow on 18 January 2023 in Carrbridge, United Kingdom (Photo: Jeff J Mitchell/Getty Images)

Scientists say human-caused climate change is partially to blame for the lengthening and frequency of the Arctic polar vortex’s southerly escapes.

The polar vortex’s strength changes from year to year. When it is strong, it stays over the Arctic region. However, a phenomenon known as "Sudden Stratospheric Warming” or “SSW” can cause it to weaken.

When this happens, the high-altitude air over the North Pole warms up. The vortex can then split into two or more freezing vortices, which have a wider geographic range and can head southward towards Canada, the US and Europe. It is known that the “Beast from the East” of 2018 was influenced by a substantially weaker polar vortex.

In fact, such an event is happening right now, according to the Met Office. However, it is currently only a modest event, which indicates that any future impact on the UK’s weather conditions would be much less dramatic.

How cold could it be?

While Britain’s recent cold snap has brought us sustained sub-zero temperatures, if a polar vortex were to head our way, it could get much colder still.

Even though the country recently experienced a stretch of harsh cold, the last truly severe winter cold wave to hit the nation was the aforementioned "Beast from the East," more formally known as Anticyclone Hartmut

It was caused by a disorganised polar vortex that broke out of the Arctic and into Central Europe, and brought strong winds, heavy snowfall, and ice from Siberia. At least 17 people lost their lives in Britain alone as a result.

How likely is another polar vortex?

Some weather maps had been indicating a "stratospheric polar vortex" could arrive by Valentine’s Day, with forecasters anticipating bitterly cold arctic winds and possibly another Beast from the East.

But the Met Office have shot down such suggestions, saying there is currently no suggestion of anything akin to 2018’s significant cold spell heading our way.

Met Office spokesperson Stephen Dixon told Chronicle Live that while signals for mid-February do indicate "some cooler weather with more frost and fog" - notably in the south - signals for snow show "there's nothing beyond what we would normally expect for this time of year."

There have been rumours that a "snow bomb" is about to hit the UK, but forecasters like BBC Weather have refuted these reports, saying such conditions aren't currently forecasted to be heading our way.

However, the BBC’s weather experts have warned of the potential for a very cold February, though current predictions are highly uncertain at the moment.

A recent BBC forecast summary said: "We are likely to return to a wetter and milder pattern in late February as high pressure weakens again and Atlantic low pressure systems return. This is very uncertain though and there remains a chance, albeit a small one, that developments in the stratosphere in late January and early February could translate to a colder set-up in late February."

What is the Met Office’s forecast for February 2023?

The Met Office’s current long-range forecast for 13 - 27 February reads:

“While uncertain, a continuation of the regional divide between the north and south is expected as the broad theme for this period. Unsettled conditions are more likely to dominate in the north while the south remains settled and drier.

“A spell of more widely spread wet and windy weather is likely to persist for several days across all areas, although wettest conditions will focus in the west. Temperatures are most likely to remain around average or above.”