Brits face up to 10 inches of snow on Thursday morning with temperatures as low as -8C making it colder than Alaska.
It is expected that the freezing temperatures remain for the coming days in parts of the country although the mercury will rise over the weekend and even reach double figures in some areas.
There are Met Office yellow warnings in place for ice and snow on Thursday which run until midday in northern Scotland, the north west of England, Wales and Northern Ireland.
It states: “Wintry showers bringing further disruption from ice and snow,” while people are told to expect travel disruption.
The advice adds: “Some roads and railways affected with longer journey times by road, bus and train services.”
There is also an ice warning for the south west of England that is in place by the Met Office until 10am.
BBC weather forecaster Nick Miller: “This weeks weather has been following a familiar pattern, most of the wintry showers have been across northern and western parts of the UK so a good covering of snow in places, especially into the higher ground but further east in the UK it has been mainly dry.
"Even though it has been sunny it hasn’t melted the frost and we are in the cold air clearly. There is a change though going into the weekend, milder air toppling in across the north and the west of the UK, warmer colours doesn’t translate into sunshine by the way, the blue hanging on for longer towards East Anglia and the south east and so here through the weekend it will stay cold."
He emphasised that there will be "hard frost" on Thursday morning saying: "Another widespread and quite hard frost as the day begins and do watch out for ice after the snow we’ve had overnight and there will be still some falling.”
Maps from WXCharts show the temperature dropping to -8C in Scotland and -5C in north west England. That is compared to Alaska where the mercury is going to be around -4C on Thursday.
There will also be up to 10 inches of snow falling in Scotland, according to forecasters, and flurries of a few inches across the west of the country.
A level three cold weather alert has also been issued by the UK Health Security Agency, warning of conditions that "could increase the health risks to vulnerable patients and disrupt the delivery of services", which is in place until 9am on Friday.
David Renard, transport spokesman for the Local Government Association, said: "As temperatures start to plummet once again, councils are ready to work around the clock to grit roads and pavements to make sure that people are kept safe and local communities can get out and about.
"Councils have stockpiled 1.4 million tonnes of salt and are using new and innovative technologies where they can to ensure those areas that are most treacherous are kept clear and safe for use.
"During these cold spells, it is those who may be elderly or who have a respiratory disease who are at more at risk of ill health and are in need of more support.
"Some people may choose to limit their heating use due to the impact of rising energy bills and so councils are again asking people to check up on those who may need more help. It could help save lives."
UK 5 day weather forecast
Today:
Frequent heavy showers, wintry inland, will push south across much of Scotland. Elsewhere, wintry showers confined mainly to coasts, with a lot of fine, cold weather elsewhere. Brisk winds in the north and east, accentuating the cold.
Tonight:
Showers, still wintry at times, becoming confined to northern and eastern areas. Very cold with hard frost and isolated freezing fog patches elsewhere.
Friday:
Wintry showers for the north, these becoming confined to North Sea coasts with time. Otherwise, fine and cold, though with isolated freezing fog patches which may be slow to clear.
Outlook for Saturday to Monday:
Becoming milder and cloudy across much of the UK through the weekend. Some rain and drizzle likely, especially in the NW. Likely remaining rather cold and dry in the southeast.
