Travel chaos is affecting commuters and holidaymakers across the country because of snow, train signal failures on the Tube, a Heathrow Express train derailing, and power supply problems at Eurostar.
Yorkshire appears to have been worst hit by the snow, with morning commuters facing difficult driving conditions.
Heavy snowfall overnight caused disruption across parts of the country and Leeds Bradford Airport to close temporarily. A spokesman for the airport said it would be shut until 9am after around 5cm of snow came down during Tuesday night. WORDS: PA
Ploughs and gritters are working along the runways and passengers should arrive as normal, but expect knock-on delays, he said.
Holidaymakers have so far been understanding about the problems caused by the difficult weather conditions, the spokesman added.
West Yorkshire Police warned people to take extra care on the roads, posting on Twitter: "Please take extra care when driving today in these cold & icy conditions. We want you to get to your destination safely."
Some motorists were forced to leave their cars after becoming trapped in snow at junction 27 of the M1 motorway. This also occurred earlier this week when snow trapped cars in Scotland.
And the weather isn't the only thing causing travel chaos around the country.
Thousands of rail passengers in London and the South East faced fresh travel misery because of another signal failure, which led to huge delays on some of the busiest routes in the country.
The problem at Guildford in Surrey disrupted South West Trains services to and from London Waterloo and delayed trains to Gatwick Airport.
Trains between Portsmouth and Waterloo were either diverted via Basingstoke and did not call at stations between Hilsea and Guildford, or they terminated at Haslemere and did not call at stations between Haslemere and Waterloo.
A train shuttle service was running between Havant and Haslemere with a limited number of taxis between Haslemere and Guildford.
Passengers were warned that journey times between Portsmouth and Guildford could be extended by up to an hour.
It is the second time in three days that SWT services have been hit after another signal problem at Waterloo led to trains being cancelled and delayed on Monday.
Heathrow Express and Heathrow Connect services between the airport and London were also cancelled on Wednesday morning after a train derailed at the train depot.
A Heathrow Express spokesman said: "All Heathrow Express, Heathrow Connect and airport inter-terminal shuttle services are currently suspended following an incident at our train depot.
"Shortly after 3am today (Wednesday) one wheel set on a Heathrow Express train came off the rails at low speed as it entered our depot in Ealing.
"Teams of engineers are now working to put the dislodged wheel set back on the track.
"Until this train is able to be cleared away, it is blocking all our other trains in the depot.
"We are very sorry to everyone affected by this.
"In the meantime passengers at Heathrow transferring between terminals can use London Underground free of charge."
Meanwhile, there were delays on London Underground today as well because of a signal failure.
Steve White, London Underground's operations director, said: "I apologise to Circle, District and Hammersmith & City line customers for the disruption to their journeys this morning caused by a signal failure at Tower Hill.
"Our engineers are working to fix the problem as quickly as possible."
Over at the Eurotunnel, there were also delays of around an hour caused by more power supply problems.
Eurostar said the issues would mean single-line working will be operating in the Channel Tunnel on Wednesday.
It said: "Delays of around an hour are currently affecting all Eurostar services today following ongoing Eurotunnel power supply issues.
"Eurotunnel power supply issues will mean single-line working remains in place today."
The problems come days after thousands of passengers were left stranded by a lorry fire on a train in the tunnel on Saturday.
More woes followed a day later as a power supply problem saw 11 trains cancelled on the service as people tried to restart their journeys.
The Port of Dover said there were no delays on cross-Channel ferry services. But due to volume and the problems at Eurotunnel, freight traffic was queuing on approach roads to the port.
A port spokesman said: "The Port of Dover, together with its major ferry partners, will do all that it can to minimise any customer delays and community impact.
"Customers are therefore advised to allow plenty of time for their journey and the community should consider using alternative local routes to move around the area where possible."
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