Londoners face a freezing start to half term as a weather system from the Arctic moves over the country causing sub-zero temperatures.
It comes as Public Health England (PHE) government forecasters extended a cold weather health alert until Tuesday.
Sunday is expected to be a particularly cold day, with a severe weather warning for snow and ice in place for parts of northern England and Scotland.
However the white stuff could fall as low as London, the Met Office has said.
Forecaster Craig Snell told the Standard: “Tomorrow is looking like a very cold day across the UK including London, conditions can be taken back to the Arctic Canada region so do wrap up warm.
“There will be sunshine and wintry showers across the north and west of the UK, down towards London and East Anglia you could see some snow as well.
“We have put out a weather warning for now and ice.
“Most of the snow will probably fall across high ground but, regardless of where you are, it is going to be a very cold day, 4 to 7C but factor in the wind chill and it will probably feel sub-zero across the country.”
On Sunday night in London temperatures could drop as low as -2C, while elsewhere the mercury could drop as low as -5C.
Mr Snell added: “It will be a cold night tomorrow night and Monday will be a little less cold, temperatures will start to recover and in the east there will be some good spells of sunshine and in will be generally dry.
“We will see some showers in the west, a mix of rain, sleet and snow.
“Tuesday will be a very cold day again, with a band of rain moving across the country that will turn to snow across the north of the UK, although it should brighten up a little bit in the afternoon especially in the west.
“From Wednesday onwards there will be a mix of sunshine and showers as temperatures start to recover for the rest of week.
“There will still be a brisk wind which will be one of the features of this week.”