Brits heading home for the holidays today are facing a “traffic nightmare before Christmas” with strike delays and heavy rain set to cause travel chaos.
Roads are already snarling up as hordes of motorists leaving town to spend the festive period with friends and family are causing heavy traffic in parts of the UK.
Many drivers are also battling a band of torrential rain which is moving north from southern England and Wales to southern Scotland and Northern Ireland throughout the day.
Downpours have already caused flooding on the likes of the M25 leading to a 10-mile queue from Woking.
Meanwhile, thousands of passengers arriving at airports in the UK are being warned they face disruption amid the start of Border Force strikes.
Members of the Public and Commercial Services (PCS) union employed by the Home Office to operate passport booths walked out on Friday at Heathrow, Birmingham, Cardiff, Gatwick, Glasgow and Manchester airports, and the port of Newhaven in East Sussex.
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RMT railway workers will then stage another strike from 6pm tomorrow, which could prevent people from making it home for Christmas Day.
Train passengers are being urged to only travel on Christmas Eve if their journey is "absolutely necessary" as the walkout will decimate services.
Adding to the problems for motorists, the Met Office is forecasting rainfall as high as 30mm throughout today.
Edmund King, AA president, says “the traffic nightmare before Christmas” on the roads is getting worse, after a slow start.
The AA reported "severe congestion" on several motorway stretches on Friday, and said industrial action on the railways has added to the number of vehicles on the roads.
King said: "Currently AA RoadWatch reports major problems across the west and north of the M25, severe congestion on M1 around Luton in both directions, M20 Maidstone, M3 near Basingstoke, M4/M5 near Bristol, M5 north of Birmingham, M60 west of Manchester and M8 near Glasgow.
"The rail strike has added to traffic congestion with a What3Words survey showing just under one third of UK adults (32%) said they will be driving to see family and friends ahead of Christmas when they would usually use the train."
Heavy rain in parts has also led to difficult driving conditions and resulted in more breakdowns than usual on the busier routes, King added.
He went on to say: "Friday and Saturday will be the busiest on the roads with some 17 million trips each day.
"Then we're expecting Christmas Day to be quieter with shorter local journeys.
"On Boxing Day traffic will pick up again with approximately 15 million trips as people head out to see friends and family."
Network Rail said trains will stop running at around 3pm on Christmas Eve.
The early closure means the last departures on some long-distance routes will be before 1pm.
Examples of last train times include 10.45am for Leeds to London, 11am for London to Edinburgh and 12.48pm for London to Manchester.
East Midlands Railway will only run an "extremely limited service" between London St Pancras and Corby, meaning there will be no trains on routes such as London St Pancras-Sheffield and London St Pancras-Nottingham.
No South Western Railway trains will run on several routes to and from London Waterloo, including Reading, Twickenham and Dorking.
Chiltern Railways will not operate any trains to or from Oxford, or north of Banbury.
The disruption is expected to cause more congestion on the roads as people switch to other forms of transport for their Christmas getaway journeys.
No trains operate on Britain's railways on Christmas Day.
The normal limited Boxing Day schedule has been scrapped due to the strike, while services will start later than usual on December 27.
Network Rail chief executive Andrew Haines has accused the RMT of causing "needless misery to its own members, to the railway and to the country's economy".
But the union, which is striking in a bitter row over jobs, pay and conditions, described the Government-owned company's offer to resolve the dispute as "substandard".
Christmas is a key period for maintenance work on the railways.
Network Rail planned a £120 million programme of more than 300 projects over the festive period this year.
It said "around 85%" of this work will still go ahead despite the RMT action.
The Border Force strikes will take place every day for the rest of the year, except December 27.
Around a quarter of a million passengers are arriving on flights at affected airports on Friday, including approximately 10,000 people who landed at Heathrow before 7am.
However, military personnel checking passports appear to be ensuring passengers are not being delayed so far.
Heathrow and Gatwick both said their immigration halls were operating as normal on Friday, while one passenger said it was the quickest he has got through border control in a decade.
A passenger with the Twitter username @olicohen wrote: "Got through Heathrow airport border control in the quickest time in 10 years.
"Being run with military precision.
"If only the army could run it permanently."
And while no issues are being reported in Arrivals at Heathrow Airport, footage shows drivers crawling through its car parks which have been backed up with "horrendous traffic" by a lane closure.
"Serious delays if you’re being met by car," said a witness who posted the video on Twitter.
Prime Minister Rishi Sunak said he is "sad and disappointed about the disruption that is being caused to so so many people's lives, particularly at Christmas time".
He went on: "When it comes to the difficult question of setting public pay, the Government has acted fairly and reasonably in accepting all the recommendations of the public sector pay review bodies."
PCS general secretary Mark Serwotka said travellers could face months of disruption unless the Government comes forward with an improved pay offer for Border Force staff.
"We think that the action at the borders is going to be very effective. We hope that the Government will therefore do the right thing and get around the negotiating table and put some money upfront," he told BBC Radio 4's Today programme.
"If not, we are raising money. We have a strike fund that means we can sustain this action. Our strike mandate lasts right up until May. We will be supporting this action up to May and we would re-ballot again if we have to.
"I think in January what you will see is a huge escalation of this action in the civil service and across the rest of our economy unless the Government get around the negotiating table."
National Highways workers responsible for motorways and major A-roads in London and the South East, also represented by the PCS, will continue their four-day walkout, which started on Thursday.
