Britain will be gripped by a cold snap this week due to an unusual meteorological event at the North Pole.

Forecasters have warned that ‘sudden stratospheric warming’ has disturbed the jet stream – allowing chilly winds from eastern Europe to blast the UK – and could last well into March.

Dr Thomas Waite, of Public Health England’s extreme events team, urged people to check on friends, family and neighbours during the cold snap, and to make sure their homes are heated to at least 18C.

He said: “With the days feeling a little longer and lighter it can be easy to forget that cold weather can still kill.

“Over 65s, those with conditions like heart and lung diseases and young children, are all at particular risk in cold weather as their bodies struggle to cope when temperatures fall.”

Met Office spokesman, Oli Claydon, said the stratospheric warming was caused by a huge rise in air temperature in an area around 18 miles (30 km) above the North Pole.

He said: “There is a very big, very cold pool of air that circulates around the North Pole – sudden stratospheric warming, as it says on the tin, is when the stratosphere suddenly warms,” he said.

“Last week we saw that take place – a sudden jump of around 50C – so that can disturb the way that cold pool of air moves around the North Pole very high up.”

Mr Claydon added sudden stratospheric warming and its impact on British weather is “not a yearly occurrence but is not unheard of”, and last impacted the UK in 2013 and 2009.

The Met Office also said there could be some frosty nights, and warned that into next week even colder air from Russia could move across the country.

Although the risk of snow is very low this week, due to the dry nature of the air, this could change after the weekend.