The mercury plummeted to -18.7C in the Scottish Highlands on Friday, marking the lowest nighttime temperature in 15 years.
And while forecasters suggest milder weather is on the way, parts of the country will continue to be ravaged by snowfall and subzero cold into next week.
Most of the UK will wake up this morning to snow, frost and heavy fog as a wintry chill continues to set in, especially in north eastern areas. And the potentially fatal weather could wreak further havoc in the coming days, according to maps from WXCharts.
The maps show heavy snow accumulating across large parts of the country on Monday morning, with depths of up to 14cm expected in 25 UK counties by 6am and the highest concentration around Invernessshire and the Scottish Highlands.
Altnaharra, a small hamlet in the Sutherland region of the Highlands, recorded the lowest January overnight temperature since 2010 on Friday night, according to the Met Office.
While snow is forecast to cover most of Scotland at the start of next week, including across Ross and Cromarty, Aberdeenshire, Dumfriesshire and Perthshire, England and Wales won’t be exempt from the extended chill.
Shap in Cumbria saw the mercury drop to -11C last night, and the north-west county is among 20 other English counties heading into a snowy and chilly next week.
Lancashire, Northumberland, Yorkshire, Cheshire, Derbyshire, Shropshire, Herefordshire, Nottinghamshire, Lincolnshire, Leicestershire, Warwickshire, Gloucestershire and Staffordshire are also forecast for snow on Monday, with up to 2cm gathering in the Midlands area.
A smattering of white could cover a stretch of the UK all the way down to Somerset and Wiltshire, through Monmouthshire and Glamorgan in Wales, and even blast the southern coastline in Hampshire with seasonal, wintry weather.
The mercury isn’t expected to rise significantly in the coming days, with the UK Health Security Agency (UKHSA) extending its cold weather health alert for the whole country until Tuesday, but record-breaking lows in the region of -20C are unlikely.
They are instead forecast to hover just below the freezing mark, at around -3C in northern Scotland and between 0C and -1C in the south by Monday morning.
Snow depths of around 6cm in Scotland and 3cm in the Midlands and the northwest are predicted to remain in place at midday on Monday, but milder temperatures and more settled conditions could begin to disperse the cold spell just 24 hours later.
Weather maps show snow depths retreating by Tuesday evening, with temperatures returning to average in southern England and remaining drifts being blown out by rain moving from the northwest over the Atlantic.
The UKHSA’s amber alerts, in place until January 14, indicate the likelihood of a rise in deaths, particularly among those aged over 65 or with health conditions.
Met Office meteorologist Zoe Hutton said cooler temperatures in the coming days would give way to milder, “recovering” weather over the remainder of the month.
“[There will be] another chilly night to come on Saturday, but then as we go into Sunday and into Monday, we can start to expect temperatures to recover somewhat,” she told the PA News Agency.
“I won’t rule out the risk of seeing something around or just below freezing again on Sunday night into Monday, but it won’t be quite so dramatic as the temperatures that we’re going to experience tonight.”
She said the UK has experienced a “particularly long cold spell” in recent days, adding: “It has been getting progressively colder each night this week, whereas looking at previous years, we’ve had maybe two or three days where things have been particularly cold.
“We’re saying it’s getting milder [next week] but by no stretch does that mean [temperatures] are going to be above average. It will just feel comparatively much more pleasant than it is at the moment.”
Today:
Frost and fog across the country, clearing to a bright and sunny afternoon. Light rain and hill snow in Northern Ireland and western Scotland.
Tonight:
Low temperatures and frost expected to develop under clear skies. Some low cloud and light drizzle in the west, slowly clearing eastwards overnight.
Sunday:
Sunny spells in the southwest and cloudy elsewhere. Rain expected to spread across the northwest and temperatures remaining chilly in the east but becoming milder elsewhere.
Outlook for Monday to Wednesday:
Dry and settled in the south, with gradually milder temperatures and the occasional raincloud. More drizzly and windy in the northwest, with the mercury also expected to return closer to the seasonal average.