By Saturday evening, 92 flights had been proactively canceled at Britain's busiest airport in a bid to allow other departures to keep to schedule.
Once again, a large majority of the flights canceled by cold weather are with British Airways. The airline has cancelled 64 short-haul flights plus a round-trip from Heathrow to New York Newark. Travellers have been re-booked on alternative departures.
BA told passengers: “We have merged a small number of flights travelling to or from Heathrow Airport.
“During cold weather conditions, aircraft have to be de-iced prior to departure to ensure that they are safe, and additional measures are taken to ensure the safety of our operation is maintained at all times.”
The airline is allowing passengers booked on Sunday to postpone to Monday, Tuesday or Wednesday without penalty.
Aer Lingus, a sister airline to British Airways, has cancelled one round trip to both Belfast and Dublin.
Lufthansa has cancelled one departure from Heathrow to each of its hubs, Frankfurt and Munich, while its budget subsidiary Eurowings has grounded a flight to Dusseldorf.
Air France, KLM, Swiss and TAP Portugal have each cancelled a round trip from their hubs at Paris CDG, Amsterdam, Zurich and Lisbon respectively.
On Saturday, more than 100 flights were cancelled from Heathrow, with others at Gatwick and London City airports.
Even though south-east England received only a light flurry of snow during the day, many flights were delayed by several hours.
The comedian Dom Joly tweeted from a British Airways 747 at Heathrow that was held up “because we need to de-ice (yeah – I laughed too) it was nearly done and they ran out of liquid... imagine if we were somewhere actually cold”.
BA departures from Heathrow to New York, Phoenix and Shanghai left around three hours late, while a Brussels Airlines service to the Belgian capital was almost four hours late.
At Gatwick, an Air Malta flight to the Mediterranean island was due to depart 13 hours late, at 1am on Sunday. Passengers on a easyJet service to Geneva endured a delay of over five hours.
Travellers whose flights are severely delayed or cancelled due to bad weather cannot claim cash compensation – but the airline must provide meals, and if necessary accommodation, until the journey can be completed.
Reaching Heathrow proved difficult for many, with all Heathrow Connect services being suspended between Paddington and the airport, and half the Heathrow Express trains cancelled.
Elsewhere on the railways, the worst disruption is on the Great Western line between Chippenham, Bath and Bristol. Trains have been cancelled or replaced by buses.
Journeys to and from Paddington are expected to be extended by at least an hour, and disruption is likely to continue on Sunday.
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