Passengers were left "in limbo" at Gatwick airport's North Terminal as a power outage added to the travel misery felt across the country.
Those who arrived at the terminal for early morning flights were grounded as they tried to get away for Christmas, while the Gatwick Express train service was also cancelled.
The chaos was compounded by a lack of information and the closure of toilets, coffee shops, restaurants and other facilities due to the power cut, passengers complained.
Graziella Vella, a six-months-pregnant make-up artist from Kilburn in north west London, was due to fly to Malta to spend Christmas with her family.
The 37-year-old said: "I am fuming and absolutely desperate - there has been no information at all and we can't make alternative plans.
"We're just hanging in limbo... at least if they said 'Nothing is going to happen, come back tomorrow', but there is no information of any kind.
"It is absolutely choc-a-bloc and in the check-in room upstairs there are 50 people queuing for the one toilet that is working."
Ms Vella said that staff initially offered to take passengers to the South Terminal, which Gatwick said was operating normally.
"Now they are just looking exasperated and worn out, there's no help at all," she added.
A Gatwick spokesman said: "Due to the adverse weather overnight, Gatwick's North Terminal is currently experiencing significant power outages across some areas including check-in.
"This is causing delays to some departing flights. South Terminal is operating as normal.
"We are investigating the cause of this issue to ensure it is resolved as soon as possible and extra staff are on hand to assist passengers.
"We are also advising passengers to leave extra time for their travel today due to weather-related road and rail disruption."
By late morning, 15 flights had been cancelled at Gatwick and some others were delayed. Passengers took to Twitter to complain, first, that there were too few announcements and secondly, that the announcements that were made were inaudible.
One angry traveller said on Twitter: "@Gatwick_Airport is a disaster zone. Power failed, no computers and baggage cannot get to planes. Floors covered with people."
The Southern train company were able to start running services to Gatwick airport by late morning, but there were no Gatwick Express services due to run from London to the West Sussex airport before 3.15pm.
A Gatwick spokeswoman said: "All North Terminal arriving flights are operating normally and all flights to and from South Terminal are unaffected.
"We are looking into the cause of the power outage. It's definitely weather-related. We are doing everything we can to get people away for Christmas and we understand passengers' frustrations.
"We have extra staff helping out in the terminals."