The prospect of a white Christmas has become more likely as Britons prepare for another Arctic blast to hit the UK this week.
Forecasters said snow and bitterly cold weather are on the way after a brief reprieve of milder conditions.
With less than a fortnight to go to Christmas, winds from the north look set to bring a band of rain and high winds on Thursday followed immediately by snow across the country.
Aisling Creevey, a forecaster with MeteoGroup, the weather division of the Press Association, said: "We've had a little bit of a reprieve over the last few days - pretty much everywhere is at risk from snow and icy conditions as the temperature drops on Thursday.
"And temperatures could be down to minus 10C in Scotland and to minus 4C and minus 5C across the country overnight on Friday."
Thursday night will mark the shift back to the big freeze, with temperatures dropping to between minus 3C and minus 6C and a widespread frost after a few days of milder temperatures, according to MeteoGroup.
Snow is set to feature throughout the weekend.
David Price, a forecaster for the Met Office, said there would be 5cm-10cm of snow over much of the country, with some higher areas of Scotland facing as much as 20cm.
Looking further ahead Jonathan Powell, a forecaster with Positive Weather Solutions, said: "Our models are showing we will see a white Christmas. The most likely places to have one are Scotland, north-east England, the east coast, the South East and London. It's going to happen."
MeteoGroup insisted it was too early to forecast a white Christmas, but the bookies have slashed their odds on it happening.
Aberdeen is William Hill's 9/4 favourite to see snow at Christmas, with Edinburgh, Glasgow and Newcastle at 3/1.
Odds on a blanket of the white stuff covering cities such as London, Leeds and Liverpool were 4/1.
Supermarkets such as Tesco and Sainsbury's had to stop taking some home delivery orders in Scotland yesterday because of the cold snap.
Plummeting temperatures and heavy snow saw parts of Scotland cut off in the last few weeks and drivers stranded on motorways.
The forecasts came as rail company Southeastern, which runs some of the country's busiest commuter routes, admitted it would "always be a challenge" to run good services in snowy conditions.
The firm, whose season ticket-holders face the biggest fare increases in the new year, faced criticism about the way it dealt with the wintry weather earlier this month.
Managing director Charles Horton said: "The South East of England was very, very badly hit by snow and ice and we were always going to struggle.
"If there is very, very heavy snow, we are always going to find it a struggle to provide a good service."
Royal Mail meanwhile announced it was spending £20 million on extra measures to handle the severe weather as it deals with the busiest posting day of the year.
The postal group said it expects to handle 130 million Christmas cards, letters and packets today ahead of the final posting dates of Saturday for second class and December 21 for first-class mail.