Respite from the chill is on the way - after temperatures plummeted to lower than some parts of the Arctic Circle last night, next week they are likely to be rather warmer.
Forecasters predict London could enjoy a relatively balmy 13C (55.4F) on Wednesday, around 6C higher than the average for this time of year.
Yet last night the thermometer hovered around minus 6.6C (20.1F) at Eskdale Muir in Dumfries in Galloway, Scotland, where around 4in (10cm) of snow has covered the Highlands over the last 36 hours.
Story continues after slideshow...
The icy conditions landed a dog in cold water after it chased a duck across thin ice.
Firefighters waded into Keptie Pond in Arbroath and broke the ice with axes after the owner informed them the pet had become trapped.
But the chill is lingering at least for tonight.
Temperatures are expected to drop to around minus 5C (41F) in rural parts of south-east England, but further north and west will be warmer with outbreaks of rain.
Paul Mott, from weather forecaster MeteoGroup, said the snow in Scotland would melt tonight before rain spreads across parts of the UK tomorrow, with snowy showers over the hills of Scotland overnight into Monday.
Temperatures at the start and end of next week will be around the seasonal average of 4C (39.2F) to 7C (44.6F) in central and southern areas, but the middle of the week will see a short-lived spike.
Mott said: "On Wednesday temperatures will be up to 13C (55.4F) in the London area, and it will be mild in the South from the middle of the week. Around 7C (44.6F) is the average at this time of year in the London area. 13C (55.4F) is above average but not unusual for this time of year, but it will be a lot milder than we have seen recently."
Despite the blip, early forecasts for next weekend and going into Christmas week suggest a rather unsettled picture, with wind and rain.
The coldest day of the winter so far was on December 5, when it reached minus 6.8C (19.8) in Benson in Oxfordshire.