London and south-east England could be colder than the North Pole this weekend as experts predict the Arctic could inch above freezing during the polar night for the first time in February since records began.
Fears of rapid polar warming that could have huge implications for global climate have been growing in recent days as the North Pole and northern Greenland have been 30C to 40C warmer than historic averages.
A weather station at Cape Morris Jesup in Greenland which is the northernmost in the world was above freezing almost all day on February 20, the Danish Meteorological Institute said.
Rod Downie, head of polar programmes at World Wildlife Fund said the Arctic was in “meltdown” following “wild and weird weather” and that action was needed now.
He 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.”
London and the south-east woke to sub-zero temperatures on Saturday morning with the mercury expected to peak at just 5C or 6C during the daytime. Overnight, temperatures are expected to fall again to as low as -4C and climb to as little as 3C during the day on Sunday.
Britain is braced for the coldest week in five years with heavy snow showers and harsh frost expected to sweet the country.
In London and the south-east the Met Office said it would be “extremely cold” from Monday night onwards with snow showers becoming “more widespread and heavier”. It is also expected to be windy.
Yellow warnings for snow are in place on Monday and Tuesday for the East and West Midlands, East of England, London and South East England.
Between 5 to 10cm of snow could fall in places, the Met Office said.
Health officials have warned of the risks of exposure as temperatures plummet and urged people to look out for the most vulnerable around them.
Dr Thomas Waite, of Public Health England’s extreme events team said: “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.
“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.”