Thousands of people are facing a nightmare journey home after the heaviest snowfall to hit the UK in 18 years caused travel chaos and closed thousands of schools.
Further heavy falls are expected during the evening rush hour on top of the 8ins (20cm) overnight that brought large parts of the country to a halt.
Sky News weather presenter Lucy Verasamy said: "It will get worse before it gets better."
She expects heavy snow in the South East to move northwards into the rest of eastern England before speading to Scotland, parts of Ireland and the South West.
Air, rail and road services have all been severely disrupted by the weather.
Major airports closed runways and all British Airways flights from Heathrow Airport were cancelled until 5pm.
All bus services in London and dozens of trains were also cancelled during the morning rush hour.
On the London Underground, 10 of the 11 lines were either completely or partly suspended.
Prime Minister Gordon Brown said the authorities were doing "everything in our power" to get the country moving again.
Motorists have been warned that disruption on the roads is likely to continue well into the night and are advised to travel only where absolutely necessary.
Transport for London (TfL) has advised people to leave plenty of time for their journeys and stagger them where possible.
Some bus services in to and out of central London are now operating but only a few.
London Mayor Boris Johnson suspended the congestion charge for the day "as a gesture of my appreciation for those who have travelled to work".
Passengers hoping to use the London Underground face significant problems with the Circle Line suspended.
The Bakerloo, Central, District, Hammersmith & City, and Metropolitan lines are part suspended while there are severe delays on the Jubilee and Piccadilly lines.
A BAA spokesman said there were significant delays and more than 650 cancellations at Heathrow airport.
British Airways said all its long-haul and short-haul flights from Heathrow were being cancelled until 5pm, with the exception of just three services.
Gatwick Airport has remained open, but there have been severe delays and cancellations, the spokesman said.
Sky News Online producer Joe Braidwood, at Gatwick, said some passengers were angry because flights were cancelled after they had checked in.
"There have been a few shouting matches. It's not a good atmosphere here," he said.
More than a thousand schools have been forced to close due to the weather, including most of the 540 schools in Hampshire and around 400 in Essex.
The Old Bailey was closed and other crown courts also suspended sittings because of "travel difficulties for staff, jurors, judges and defendants".
More than one in five people took the day off work because of the snow, a survey by employment law firm Peninsula suggested.
Low temperatures overnight mean the snow in the east is not expected to melt, causing frost and black ice by dawn, Verasamy said.
"The South East will turn drier and calmer tomorrow but temperatures will plunge and driving conditions will be treacherous," she warned.
"Scotland will get snow, as will parts of Ireland and the South West.
"There will be sleet and rain in the South West on coastal areas and some snow inland.
"The rest of the week is looking very wintry with further sleet and snow to come."
Britain has been warned more snow is on the way after wintry weather brought parts of the country to a standstill.
Questions have been asked about whether much of the disruption could have been avoided after London ground to a near halt on Monday.
Buses were cancelled and train and Tube services were badly hit when thick snow blanketed the capital.
An estimated one in five workers took the day off and thousands of schools in the south of England closed. Many remain closed on Tuesday.
Snow has created hazardous conditions in parts of the north while plummeting overnight temperatures in the south meant ice prompted the Highways Agency to repeat its warning to postpone all but essential journeys.
The lowest recorded temperature was in Chesham, Buckinghamshire, where it fell to minus 10.1C (13.8F) overnight.
There is likely to be further disruption this week with another wave of snow expected to sweep from south to north. But while many children were delighted to have a day off to play, some said school closures were adding to the problems for working parents.
Margaret Morrissey, of the Parents Outloud campaign group, said: "It is terribly difficult for parents. You've got to go to work and you've got the added problem of what to do with the children."
Stephen Alambritis, from the Federation of Small Businesses, said the economy could lose as much £3.5 billion this week as a result of weather-related disruption.
He called for more debate on solutions, adding: "One of the world's biggest economies should not be grinding to a halt."
I guess with the relative size of the UK and the USA when this weather hits it effects the UK more because most of the whole country suffers - in the US it is generally a much smaller part being messed up at any one time so the economy does not hurt as much.
Indeed. These much smaller nations can get hammered all at one time. In the US it generally effects a region 1/5 of the nation's size at one time at best.
This is how I get creative in the winter with snow. Get out and be creative and have a blast. This is a Snowasaurus. It's a brontasaurus made of snow. Enjoy!! Wanted to spray him green with food coloring but didn't have time the sun was melting the snow and we wanted to go sledding.