Snow UK
A snow plough drives along a road covered in snow, in Northumberland, England, in a file picture. Image Credit: AP file

London: The UK is preparing for a late blast of cold next week that could mark the start of an unusually chilly March.

Snow and ice warnings are in place for the UK from Monday, with temperatures set to drop far below seasonal norms. An extreme weather event known as “sudden stratospheric warming” “- which can cause extreme cold in the Northern Hemisphere “- risks prolonging the cold spell until the end of March.

The turn in weather comes at the end of a mild winter that helped the UK, along with the rest of Europe, to retain adequate supplies of gas and avoid rolling blackouts during the energy crisis. Still, a cold front could pressure those inventories. It also comes as a storm has brought snow to the northeast US, including New York.

“Temperatures will drop to below normal across the UK over the weekend as a cold north to north-easterly develops,” said Amy Hodgson, a meteorologist at Atmospheric G2.

For the rest of the month, forecasters see mounting odds of sudden stratospheric warming influencing the weather. The phenomenon, which occurs around six times per decade, refers to rapid warming high above the Earth’s surface, which causes a circulation of winds known as the polar vortex to break down.

Sudden stratospheric warming

That can cause cold air to descend very rapidly and can lead to changes in the weather on Earth, and result in extreme bouts of freezing temperatures and snowstorms.

Meteorologists saw signs of sudden stratospheric warming taking place from late last month. As the extreme weather event “- high up in the stratosphere “- comes to an end, its colder impacts will continue to be felt across Europe, according to Maxar meteorologist Matthew Dross.

In 2018, the UK’s so-called ‘beast from the east’ was caused by sudden stratospheric warming. At the time, temperatures in the UK plunged as low as -12 degrees Celsius and caused issues with energy infrastructure. It also resulted in the deaths of 10 people.

The Met Office’s outlook suggests that March is likely to be colder than average, but any impact from sudden stratospheric warming is still uncertain, said the national forecaster. Still, the Met Office sees increased chances snow, frost and fog for parts of the UK.

“The exact positioning of the high pressure will be key and will greatly affect what weather we see in the UK,” said Mark Sidaway, deputy chief meteorologist at the Met Office.