Parts of south-east England could end up colder than the North Pole this weekend, as forecasters predict that the Arctic could inch above freezing point during the polar night for the first time in recorded history.

The North Pole and northern Greenland have been 17-22C (30-40F) warmer than historical averages in recent days, adding to fears of rapid polar warming that has huge implications for global climate. The northernmost weather station in the world, Cape Morris Jesup in Greenland, was above freezing nearly all day on 20 February, according to the Danish Meteorological Institute.

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Rob Downie, the head of polar programmes at WWF, said: “The Arctic is in meltdown and wild and weird weather is happening in front of our eyes. We need to take responsibility as evidence shows us that sea ice is in severe decline due to our changing climate. We need to act now to cut carbon emissions and ramp up efforts towards a renewable future to secure a future for Arctic wildlife and people.

The warning came as health officials spoke of the risks of exposure as temperatures plummet over the weekend and Britain faces the prospect of the coldest end to a winter in five years. Freezing air from Siberia is forecast to envelop the country next week, bringing significant and “disruptive” snowfall. The Arctic blast, nicknamed “the beast from the east”, will cause temperatures to drop below zero from Sunday night, with some areas experiencing lows of -8C (17.6F), and snow forecast to fall in London and the east of England.

Met Office (@metoffice) Cold air from northern and eastern Europe is heading west over the next few days. By Monday temperatures in the UK will be close to or below freezing, ❄️even in the middle of the day pic.twitter.com/Ov1Ekk8agz

On Friday, Public Health England (PHE) told people to look out for the most vulnerable. “Cold temperatures, indoors and out, pose real health risks to many and every winter we know that thousands of people get ill and even die following exposure to cold conditions,” said Dr Thomas Waite, of PHE’s extreme events team.

“It’s critical that if you know anyone over 65, with young children or who has heart or lung conditions, that you keep an eye on them and think what help they may need. Staying warm by heating your home to at least 18°C can be crucial to staying well.”

The Met Office issued yellow warnings of snowfall – the second most severe on the forecasters’ scale – for the early part of next week. It warned of possible travel delays and power cuts, and said some rural communities could be cut off.

“Cold weather is currently established across the country with widespread overnight frosts,” the Met Office’s chief operational meteorologist, Paul Gunderson, said.



“However, colder conditions are expected to extend westwards across England during the weekend bringing a significant, and prolonged period of wintry weather. During Monday and Tuesday, snow showers are expected to move into eastern areas, before spreading westwards across England.”

While not everyone would see snowfall, he said, as much as 10cm was possible in eastern and south-eastern counties. “These will also be accompanied by bitterly cold temperatures, and a significant wind chill. These cold, wintry conditions are then expected to continue on Wednesday, and likely beyond.”

On Friday, the London mayor, Sadiq Khan, said he had opened emergency shelters to protect rough sleepers. “With temperatures dropping across London tonight and this weekend, I’ve opened emergency shelters to ensure people sleeping rough have somewhere warm to stay,” he tweeted.

Sadiq Khan (@SadiqKhan) With temperatures dropping across London tonight and this weekend, I’ve opened emergency shelters to ensure people sleeping rough have somewhere warm to stay. #HelpRoughSleepers https://t.co/6egXAhLtKt

A Met Office meteorologist, Martin Bowles, said the temperatures could be the lowest in late February since 2013.



“It is quite unusual, particularly as it’s quite late in the season. We refer to 1 March as being the first day of spring and of course 1 March will be right in the middle of this cold spell, so spring will be postponed for a couple of weeks,” he added.

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