Tuesday night could be the coldest of the year so far, the Met Office has warned, with temperatures set to drop as low as -15C (5F).
It would beat the current lowest temperature of -10.4C (13.3F), recorded at Drumnadrochit near Inverness in the Highlands in the early hours of 19 January.
The lowest temperatures on Tuesday are expected to be in sheltered Scottish glens, especially where there is fresh snow cover.
It comes as the Met Office – and the UK’s Health Security Agency (UKHSA) – issued warnings for snow and ice for large parts of England, Scotland, Wales and, Northern Ireland, this week.
Arctic air is sweeping across due to a “highly amplified” jet stream, mixed with an area of lower pressure over the Mid-North Atlantic, which is pushing air up into northern areas and back down towards the UK.
UK weather: The latest Sky News forecast
A yellow warning is in place for London, the Thames Valley, East Anglia, parts of the Midlands and South Wales from 9pm on Monday night until 10am on Tuesday.
An identical one will be in place in Northern Ireland at the same time.
Another yellow warning is in place for much of Northern and Eastern Scotland and North East England and is set to remain in place until 10am on Wednesday.
South West England and South Wales will be covered by another yellow warning for snow all day on Wednesday, and a few centimetres of snow could fall in those areas.
‘Much colder than we would expect’
North England, North Wales, most of Scotland and Northern Ireland will also be covered by a yellow warning for snow between 3am on Thursday and 6pm on Friday.
Met Office spokesman Grahame Madge said temperatures would be “much, much colder than we would expect at this time of year”.
He said: “We expect these conditions to remain in place until at least next weekend and possibly longer because sometimes these conditions can be quite stubborn and not easily subject to change.”
The Met Office warned travel disruption is likely and journey times by car, train and bus may take longer than usual. Some rural areas could also become cut off from the national power grid.
Be the first to get Breaking News
Install the Sky News app for free
UKHSA has issued a level three cold weather alert for the whole of England, which is likely to be reviewed in the coming days.
The agency’s head of extreme events and health protection, Dr Agostinho Sousa, said people should check on vulnerable relatives and told pensioners and anyone with an underlying health condition to heat their home to at least 18C (64F).
