EasyJet and Ryanair expect delays to flights from London's Stansted and Luton airports on Wednesday after runways were closed due to snowfall and freezing conditions.
London's third largest airport, Stansted, located 50 kilometres northeast of London, closed its only runway for around three hours on Wednesday to clear about an inch of snow which fell overnight in southern England.
Around 40 flights were cancelled with many more likely to be delayed.
Irish budget carrier Ryanair, the largest airline at Stansted, said it expected to resume flights from the airport during the morning but that the majority of its services from Stansted on Wednesday could be delayed.
"Northern Essex seems to have got the worst of the snow and we had to shut the airport at 0600 GMT," said a spokesman for Stansted airport, which is owned by Ferrovial's Heathrow Airport Holdings.
"The mornings are busiest at the airport so there will be a knock-on effect and delays to more flights this morning."
Stansted, which is predominantly a low-cost leisure travel airport, moves around 18 million passengers a year.
Smaller Luton airport, 56 kilometres north of central London, was forced to close its only runway for an hour on Wednesday.
British low-cost airline easyJet, the biggest operator at Luton, said it had seen little disruption at Luton but expected some delays at Stansted.
Ryanair said it also expected some delays to its services from Luton due to the "very limited movements" on its single runway.
Aberdeen airport in Scotland also closed briefly on Wednesday but London's Heathrow, Gatwick and City airports said they were operating as usual.
Heathrow Airport Holdings, formerly BAA, was widely criticised after heavy snowfall paralysed Heathrow, Europe's busiest airport, in December 2010, leading to a spate of flight cancellations after runways were closed due to snowfall and freezing conditions.