The UK continues to be gripped by a deep freeze as sub-zero temperatures could bring the coldest night of the year, forecasters warned.
Arctic air hovering across the UK will cause the mercury to drop to minus double figures in parts of Scotland on Thursday night, while snowfall is forecast to cause significant travel disruption on Friday.
A severe weather warning for snow is in place across parts of northern England and southern Scotland on Friday morning, but the Met Office has since warned this could be extended.
A separate weather warning for ice remains in place across much of the UK until 11am on Thursday.
National weather forecast for 28th December 2017
On Wednesday and into the early hours of Thursday parts of the country faced travel misery and power outages as freezing conditions struck Britain.
Temperatures are now expected to plummet to -13C in parts of Scotland, Met Office spokeswoman Nicola Maxey said.
She also warned that a yellow warning of snow on Friday could be upgraded to amber, with up to 10cm of snow due to fall.
She said it is “probably central areas of England” that will be affected by the heaviest snowfall as the working week comes to a close.
Hundreds of passengers were stranded at Stansted after the airport was forced to temporarily ground planes
But Ms Maxey warned the country could see the “coldest night of the year so far” before the snow blankets parts of the country.
“The coldest temperature we have seen this year is -13C in Scotland, and we are likely to see temperatures slightly below that,” she added.
“But we are not talking about those extremes in the town and city centres, it is out in rural areas, more exposed areas, particularly over lying snow where you see temperatures drop the most.”
The Met Office said temperatures reached as low as -6C overnight across parts of northern Ireland, while much of the UK was between -1C and 1C.
Temperatures are expected to remain below freezing at -1C in London overnight on Thursday.
Met Office forecaster Charles Powell told the Standard: “A band of rain will start to work its way in across the west by Friday morning. This will bring snow in the north east as that rain moves in and meets cold air.
“We could see snow as far south as the North Midlands and north to Scotland.”
A yellow weather warning for snow is in place from 3am through to midday on Friday, with roads, railways and air travel likely to be affected, the Met Office said.
The Met Office forecaster said Londoners could expect “a brighter day” on Thursday.
He added: “It will be a dry start to Friday in London then increasingly wet through the morning.
“It will be quite windy as that rain moves through. We are not talking gales but tomorrow will be another breezy day.”
Brits already faced travel disruption earlier this week as Stansted and Luton airports saw flights delayed and cancelled on Wednesday.
Elsewhere, latest figures from Western Power Distribution (WPD) and Scottish and Southern Electricity Networks (SSEN) showed nearly 13,000 homes remain without electricity.
The latest snowfall to blanket the UK came just a fortnight after after hundreds of schools were closed, homes were left without power, and travellers were stranded or forced to stay indoors when a cold snap hit the UK.