Britons hoping for festive snow may miss out again this year with a mild but unsettled Christmas now likely.

Strong winds and rain are forecast this weekend with stormier conditions threatening to set in on Boxing Day.

Last-minute Christmas shoppers will however enjoy a burst of mild spring-like weather over the next few days.

The Met Office predicts temperatures of around 12C (53.6F) until the weekend with some forecasters saying 15C (59F) is possible.

After a freezing start to winter milder winds could bring the warmest Christmas on record beating the 60F (15.6C) set in Devon in 1920.

Met Office forecaster Oli Claydon said it is still too early to give a definitive weather outlook for the big day.

He said: “It is going to be much milder this week compared to the recent cold weather with temperatures in double figures across northern and southern Britain and slightly cooler in central regions.

“This is due to a tropical maritime airflow and high pressure to the south and west of the UK which is blocking the usual tracks of unsettled conditions from the Atlantic and giving benign, settled weather.

“However is looks like turning unsettled on Saturday with strengthening winds and rain in the north, it looks like the weather will turn more unsettled from Boxing Day.

“In terms of snow on Christmas Day, it is still early to say with any certainty.”

The weather is expected to stay largely settled this week although forecasters warn of stormier conditions from the weekend.

While chances of seeing snow on Christmas Day are looking ever more scarce some experts say the definitive single flake is still possible.

Exacta Weather’s James Madden said: “Despite a milder week and a fairly quiet spell of weather it is likely to turn colder from the north around the festive period.

“This could coincide with some rather unsettled and windy weather that will approach from the west.

“The chances of a white Christmas are more likely in northern and western areas.”

Mild air from the Atlantic will arrive laden with moisture which will freeze overnight bringing stubborn fog over the coming days.

The Met Office has issued a severe weather warning into Tuesday morning with thick mists threatening to spark travel delays and airport disruption.

Government weathermen say fog will be an issue through the week thanks to a lack of wind and cold nights.

Met Office chief forecaster Steve Ramsdale said: “Fog is expected to form widely across southern and central England and some eastern parts of Wales on Monday evening, persisting overnight into Tuesday.

“Slower journey times are likely with delays possible to bus and train services.

“Some delays or cancellations to flights are also possible.

“With light winds and clear skies fog is expected to form quite widely on Monday evening with visibility falling below 100 metres in places.”

Mr Madden added: “The next few days will see some very dense fog developing over the UK and these stubborn patches could linger for some time, central and southern areas are most at risk.

“This widespread fog could cause problems in the run up to Christmas and in places may struggle to clear for several days.”