Yellow alerts are in place in other areas, as people face a wintry start to 2026.
Amber warnings for heavy snow showers in parts of Scotland have been issued by the Met Office.
They are in place from midday on Friday to midday on Saturday.
A yellow weather alert for snow and ice is in place throughout Friday morning for an area covering London, Greater Manchester and Cardiff, while a yellow warning for ice in the southwest of England was issued by the Met Office on Friday morning that runs until 10am.
In Scotland, the chilly conditions have led to the closure of several snow gates in the north of the country, stopping travel on some roads.
Traffic Scotland said the snow gates on the A93 Braemar-Glenshee, A939 Tomintoul-Cockbridge, B974 Cairn O'Mount-Fettercairn and at Bealach na Ba were shut on Friday morning.
The areas covered in the amber warnings include Angus, Perth and Kinross, Aberdeen, Aberdeenshire, Moray, and the Highlands.
Around 10-20cm of snow is likely at low levels, with 30-40cm possible on high ground, while winds could lead to temporary blizzard conditions, according to the Met Office.
It added that some delays and cancellations to rail and air travel are likely, as are power cuts and disruption on the roads, while some rural communities may be cut off.
Chief Superintendent Scott McCarren, Police Scotland's head of road policing, said: "Our advice is to plan ahead and consider if your journey is really necessary during the bad weather or if it can be delayed until conditions improve.
"If you need to travel, please drive to the conditions, be prepared for delays and allow extra time for your journey.
"Please don't drive through road closures, the decision to close roads is not taken lightly and is done for public safety."
South of the border, snow up to 5cm could cover some areas, especially on higher ground in parts of North Wales and northwest England.
Separate yellow warnings are in place for Northern Ireland between midnight and 10am on Friday.
Weather warnings were already in force on New Year's Day in Scotland, with a yellow warning of snow and ice covering the northern part of the nation.
The Met Office said 10cm of snow could have accumulated by Friday morning, while up to 20cm could build up above 200 metres.
The warning is in force until midnight on Friday and at the weekend it extends further south, covering the area down to Perth and southerly parts of Argyll and Bute until midnight on Sunday.
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Meanwhile, the UK Health Security Agency (UKHSA) has issued health warnings for the start of the year.
It previously issued amber cold health alerts in the North East and North West of England.
However, yellow alerts have been upgraded to amber across the East Midlands, West Midlands, South East, South West, East of England, Yorkshire and the Humber, and London.
These warnings are in place until 10am on 6 January.
The UKHSA said it means the weather is "likely" to cause significant impacts across health and social care services, including a "rise in deaths" among those with health conditions or aged 65 or over.
Warning: This article contains details you might find distressing
Research carried out and shared by the YMCA'S Dignify Project shows that the age of children seeing sexual content on the internet is getting younger.
The project, which works to protect children and young people from the harmful effects of pornography, said children "can't unsee what they've seen".
The average age of children seeing pornography is 12, according to Dignify.
Nicola Lee, from Dignify, told Sky News that when delving "deeper" into their data, they have discovered that some children who first viewed pornography aged five and under are also "reporting addiction to pornography".
"So it wasn't just a case of they saw it at that age," Nicola added, "it actually has developed with them into their older years, and they're now telling us that they have an addiction."
One young woman, Shaniah Williams, told Sky News she first saw pornography at just seven years old, after being "exposed to harmful sexual behaviour" when she was six, which prompted "a curiosity" to search online for answers.
She described content being available to her on "certain platforms", and by the age of eight, she was watching extreme pornography.
By 12 years old, she said she was addicted: "I didn't understand why I was so low. Consuming more of this material kind of kept me sane… but the thoughts wouldn't stop every minute of every day. I just wanted it to stop."
'I didn't know humans looked like that'
Despite having restrictions on devices, Shaniah said the material she saw as a child left her terrified and confused, and she subsequently suffered from depression and suicidal thoughts.
"I could look at the kids in the playground and tell you which one had been exposed to it, just due to their language," she explained.
"I used to wish I could be like the girls who hadn't. I was in the dark, in a prison of my own making."
Shaniah is appealing to parents to start conversations with their children.
"It was scary. I didn't know human beings looked like that," she said. "I'm a child, I've not seen that. I thought someone was killing the other person. I thought it was torture."
"It took my childhood," she added, "it's gone. I'm not getting it back. But it doesn't mean other children can't have that. So I beg of you, parents - please. For their sake."
Children find pornography 'unintentionally'
According to Dignify's research, most children find pornography online "unintentionally", for example sent in a group chat, found through a link from another platform, or shared by a stranger.
"We do have children and young people who are seeing pornography," Nicola said.
She added: "A third of those who have seen pornography have seen it in primary school. It's scary, it's really scary as a parent to think, wow, my child might have seen pornography.
"But they may not have. So that curiosity, we don't want to spark it."
Dignify are also encouraging parents to think about "age and developmentally appropriate" conversations around the issue - and have developed a "roadmap" guide to follow.
In the early years, they advise talking about screen use and safety, and where screen use is happening to experience it as a "shared moment", such as playing games together.
As well as parental controls and privacy settings on devices, Nicola also recommends being in the same room if a child is going to be by themselves on a screen to "understand what they're looking at".
'Exposed within months at secondary school'
The problem, however, is also seemingly widespread in schools.
Flossie, 17, told Sky News she was overwhelmed by the volume and extremity of content circulating among pupils in her secondary school.
"Within the first three months, I was exposed to literally everything on social media - hardcore pornography, violent videos," she said.
One clip that went viral in her school showed a woman being beheaded. Another involved bestiality.
She said she had no choice in seeing it. "I got off the bus one day, and it was shoved in my face. I was 12. I had to go home from school because it was so disturbing."
Flossie is now part of a legal challenge calling for smartphones to be banned in UK schools, arguing that children cannot be protected while devices remain in classrooms, playgrounds, or even on the school bus.
"It's the kids doing this to each other. And the only way it's going to stop is if they take the phones away. It takes one child in a whole school," she said.
'Year 7 pupils will see things they can never unsee'
Will Orr‑Ewing, who is also involved in the challenge, said more than 250 headteachers support a potential judicial review of government guidance.
"If the secretary of state wanted to, it doesn't require any primary legislation. She can update the guidance, and it could be solved tomorrow," he said.
He warned that every new school year brings another wave of children at risk: "Every September is a new Year 7 and a large percentage of those children are going to see things they can never unsee."
Mr Orr-Ewing explained that while most parents support restrictions, a "vocal minority" believe smartphones keep children safe - something he called "a myth".
"The evidence is that the vast majority of harms come through the smartphone. Parents think they're keeping their kids safe, but they are sadly making them more in danger by giving them a smartphone," he said.
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A Department for Education spokesperson said: "We support headteachers to take the necessary steps to prevent disruption, backed by our clear guidance. Research from the Children's Commissioner shows 99.8% of primary schools and 90% of secondary schools already have policies in place restricting the use of mobile phones.
"Through the Online Safety Act, we have taken some of the boldest steps anywhere in the world to ensure children have age-appropriate experiences online, protecting them from harmful content.
"We are striking the right balance: protecting children while ensuring they can safely benefit from the digital world, without risking isolation or cutting off access to vital services, especially to the most vulnerable."
If you have been affected by any of the issues raised in this story, help and support is available.
You can call Samaritans free on 116 123 anytime day or night. You can also email jo@samaritans.org or visit www.samaritans.org to find support online.
Greater Manchester Police officers were called to reports of a disturbance at an address in Tarn Drive at "around 11.55pm" on Wednesday where they found a man with "injuries consistent with a stabbing".
He died at the scene despite the efforts of emergency services.
Anthony Junior Murray, 25, has been charged with murder and possession of a bladed article.
He has been remanded in custody and is expected to appear at Manchester Magistrates' Court on Friday.
A woman in her 20s was also arrested and has been bailed pending further enquiries.
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Greater Manchester Police is urging all those with information or relevant CCTV, doorbell or dashcam footage to come forward.
The force said: "The investigation remains ongoing."
It will be offered to youngsters alongside the MMR jab, which protects against measles, mumps, and rubella.
It's a combo that's long been available to children in other countries, including the US, Canada, and Australia, and the move has been welcomed by health experts.
The UK rollout was recommended by the Joint Committee on Vaccination and Immunisation (JCVI) in 2023, and in England alone hundreds of thousands of kids will be eligible from today.
Health Secretary Wes Streeting said it will "make a real difference for children and families".
He said: "While chickenpox can be irritable and difficult for children, it can also be extremely serious and occasionally even fatal.
"The great thing about this new vaccine is that it combines the vaccine for chickenpox with MMR, which means that families can access this jab for their children, aged between 12 and 18 months."
Who is eligible for the vaccine?
Children born on or after 1 January 2025 will be offered two doses of MMRV at 12 months and 18 months.
Those born between 1 July 2024 and 31 December 2024 will be offered one dose at 18 months and another at three years, four months.
Children born between 1 September 2022 and 30 June 2024 will be offered one dose at three years, four months.
A single-dose catch-up scheme is also planned for children born between 1 January 2020 and 31 August 2022.
NHS England said GPs will be contacting families as part of the routine childhood vaccination programme.
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Dr Gayatri Amirthalingam, deputy director of immunisation at the UK Health Security Agency, said the jab "has been shown to be highly effective" in other countries, "with a good safety profile".
Dr Claire Fuller, national medical director for NHS England, added: "This is a hugely positive moment for children and their families, providing protection against chickenpox for the first time and adding to the arsenal of routine vaccinations we give to children to safeguard them against serious illnesses."
The vaccine will "keep more children safe and in school", she added.
The new high was reached within a half hour of the first day of trading in the new year.
The Financial Times Stock Exchange (FTSE) 100 comprises the hundred most valuable companies listed on the London Stock Exchange.
Notable constituents include lenders such as Barclays, Natwest, HSBC and Lloyds and supermarket chains Tesco, Marks & Spencer and Sainsbury's. The index is also largely made up of mining and international oil and gas companies.
"This is a historic moment and already makes 2026 one of the most significant years for the blue-chip index since its launch in 1984," said Dan Coatsworth, the head of markets at investment platform AJ Bell.
Boosting the top flight on Friday morning were share price rises from aerospace company Rolls-Royce Holdings and mining company Fresnillo, the company which saw the single largest rise last year.
A run of records
It comes off a record-breaking year for the FTSE 100, in which it closed at an all-time high 41 times, according to data from the London Stock Exchange Group (LSEG).
In 2025, it had its best year since 2009, outperforming rivals including the S&P 500, the US index containing the most valuable companies in the world.
Before smashing the 10,000 mark, the previous symbolic level of 9,000 was passed in July.
Expectations of cheaper borrowing from interest rate cuts and a weaker pound at times helped FTSE 100 company competitiveness as it made buying sterling-priced shares better value.
Why the new year rise?
Policy announcements by Rachel Reeves have been credited with part of the new year rise.
"Breaking through the 10,000 level is the best New Year's present Chancellor Rachel Reeves could want," Mr Coatsworth said.
"She has been banging the drum about the merits of investing over parking cash in the bank, and the FTSE 100's achievements just go to show what's possible when buying UK shares."
The change to cash ISAs announced in the budget, whereby savers can only put up to £12,000 tax-free a year, is intended to get people to put their money in the stock market.
New measures mean banks and building societies will also be empowered to give customers financial advice.
After the initial 10,000 threshold was reached, the FTSE 100 fell back slightly to 9,982 later in the morning.