The Christmas hopes of millions of Britons hang in the balance today as, undeterred by continuing Arctic conditions and the prospect of further snowfalls, they begin their holiday travels across the UK by road, rail and coach.
At the same time, despite the fact that thousands of minor roads remain icy and hazardous, freight companies and postal services are racing to deliver a backlog of millions of presents, as well as essential supplies, while fears of fuel, food and grit shortages continue to build.
Retailers, meanwhile, are looking at today – the most important shopping day in the immediate run-up to Christmas – as their last chance to recoup some of their dramatically reduced seasonal takings. The hoped-for shoppers will put further strain on the country's frozen infrastructure.
And at airports the situation for hundreds of thousands of passengers remains uncertain as major hubs, including Heathrow, struggle to clear backlogs and bring an end to the misery of delays and diversions.
Motoring associations and travel companies predict that today will be the busiest of the year for travellers, with a peak expected at about 10am. People forced to stay in Britain by delays to air and Eurostar travel are expected to add extra strain to the overburdened road and rail network.
The AA estimated that almost 14 million cars would be clogging up the roads, with a third covering more than 100 miles.
The organisation has been working at twice its usual rate over the past few days, receiving 21,000 call-outs yesterday compared with 9,500 for a normal Wednesday – and it is advising motorists to expect their journey times to be doubled.
While main routes are now largely clear of snow across the country, some routes remain treacherous – and with more snow forecast for large parts of Wales, the Midlands and the South, conditions were expected to worsen.
"We are expecting it to be the busiest day of the year," said an AA spokesman. "If anything there will be even more people who have not been able to return to their families until now."
The coach operator National Express also predicted that today, particularly around mid-morning, would be the busiest on the roads. With an increase in passengers frustrated by plane and train delays in the cold weather it said it had laid on 200 extra coaches with 40 per cent more services than usual for an estimated 50,000 passengers. Train services appeared to be improving yesterday. Seventy per cent of trains were running on time across the UK although there were still disruptions, with Virgin Trains having to cancel some London to Birmingham and Manchester services.
"It is an improvement. Things are running better," said a Network Rail spokesman. "There are still some amended timetables in place and disrupted services. We will be working hard with the train operators to run the best service and keep the infrastructure operational."
While the Midlands endured blizzards yesterday, the Met Office said it was expecting it to be a dry day for most areas today though it would remain bitterly cold, rarely reaching above freezing and dropping to as low as -20C in parts of the Highlands.
Later in the afternoon, however, it was forecast that the South-east, including parts of Suffolk, Essex, Kent and Sussex would have some snow showers and strong winds.
"Wherever you're heading, allow plenty of extra time, as the last thing you want to do is rush in these conditions," said Darron Burness, head of AA Special Operations. "Spend some time checking your car over, as up to half of all breakdowns could have been prevented and, as well as the Christmas presents, don't forget to carry all the essential winter kit, especially plenty of warm clothing and a fully-charged mobile."
Driving conditions will be tricky early on with localised fog patches, but it will clear during the morning to leave a dry day – good for those hoping to travel.
Generally dry, but the South-east is likely to be hit by more snow. The North could also see light snow showers.
The South-east will have more cloud meaning higher air temperatures. The rest of the country should have clear skies, with more frost overnight.
Britain feels the strain
14m Number of cars expected to clog roads as millions of travellers journey home for Christmas.
75 Councils, among a total of 205, still waiting for orders of grit.
13 Thefts of heating oil reported by Avon & Somerset police as the cold weather continued to drive up prices.
200 Extra coaches laid on by National Express every day as more than 50,000 travellers abandoned train travel.
14,000 Extra delivery rounds made daily by Royal Mail as it battled to clear a backlog of presents.