Christmas getaway travel disruption is expected, with millions of car journeys under way and major London railway stations set to close on Sunday.
The AA estimated that 16.4 million car journeys will take place on Saturday and warned of “lengthy jams”.
And rail disruption is likely on Christmas Eve as two of London’s railway stations, King’s Cross and Paddington, will be shut due to engineering works.
The closure of London Paddington will continue until Wednesday, meaning no mainline trains will serve Heathrow Airport.
At the Port of Dover, waiting times reached 90 minutes at border control on Saturday morning, but the queues have since cleared.
The port said there had been a surge in demand for ferries after the Channel Tunnel rail link was closed on Thursday due to unscheduled industrial action by French workers, which ruined the travel plans of tens of thousands of people.
Meanwhile, drivers are being warned to expect delays on the A1 in Northumberland after a serious crash.
The road was closed in both directions on Saturday morning after the incident, which happened between the A1167 and B1340 near Belford.
The Met Office has warned Christmas Eve travel plans could be affected with heavy winds set to batter parts of the country.
Gusts as high as 70mph are due to hit the north of Scotland and northern and central areas of England.
Two separate yellow weather warnings for wind have been issued, saying people should expect travel disruption, damage to buildings and power cuts, while the rest of the country may see showers.
Meteorologist Liam Eslick said: “People should make sure to leave more time, especially in exposed areas, it could affect rail networks and ferries.
“People travelling on roads should take care and stay away from high-sided vehicles, and for people who are at home and are going for walks, stay away from coasts.”
A yellow weather warning for rain is currently in force covering much of Wales, with forecasters warning that flooding and travel disruption is possible, and will last until 6pm on Christmas Eve.
Between 20 to 40mm of rain is expected widely and 60 to 80mm on higher ground.
Another yellow weather warning for rain is in force for western Scotland until 11.45pm on Saturday, with 20 to 55mm of rain expected widely and 80 to 100mm on higher ground.
Motorists have been advised by the RAC to travel before 11am or after 6pm if possible to reduce the chance of being stuck in long queues.
Eurostar, which operates passenger rail services to and from London St Pancras, is operating two extra trains per day between London and Paris including on Christmas Eve to help people whose trains were cancelled on Thursday.
Vehicle-carrying train service Eurotunnel is running its usual timetable but is only accepting customers who have pre-booked.
Shadow transport minister Louise Haigh said the domestic rail infrastructure has been “totally underinvested in”, causing “record delays and cancellations”.
She told Times Radio on Saturday that anyone who has tried to catch a train in the last couple of years will “almost certainly” have experienced delays, cancellations and poor service because the Government has “presided over the managed decline of our railways and has been totally prepared to accept status quo”.
Ms Haigh said the Labour Party has set out plans to reform railways to bring them into public ownership and “to bring decisions around infrastructure and the operations of the railways together”.
She added: “The infrastructure has been totally underinvested in. And as a result, we are seeing these record delays and cancellations. And people will be experiencing that themselves as they attempt to travel home today and tomorrow for Christmas.”
A Department for Transport spokesperson said: “We know that Christmas is a busy time on our roads – and we work closely with train operators, ports and airports to ensure people can get to where they need to be during the festive period.
“To keep congestion to a minimum, National Highways is ensuring more than 98% of motorways and A-roads are roadwork-free, with over 96% of the rail network also open during Christmas and New Year.
“This Government has made unprecedented investment in transport infrastructure and to suggest otherwise is factually wrong.
“We are providing a record £44.1 billion for Network Rail to run a safe rail network.
“Our Network North plan – backed by £36 billion – will further revolutionise the country’s transport infrastructure with investments in hundreds of local transport projects that matter most to people.”