People are urged to look out for friends and family amid unseasonably cold temperatures this week.
Image source, Getty ImagesThe Met Office has warned that severe cold weather is set to hit the UK this week, with overnight temperatures plummeting to -6C (21F) in some places.
Snow is likely in northern Scotland, although temperatures will be low enough to make it a possibility anywhere in the country.
Frost and ice are also expected.
People are being urged to use their heating, despite rising energy prices, and to look out for people who are especially vulnerable.
Health care providers are also being told to implement cold weather plans under a level three cold weather alert, between 18:00 GMT on Wednesday and 09:00 on 12 December in most parts of England.
A yellow weather warning for snow is also in place for northern Scotland on Wednesday.
BBC Weather’s Simon King said that, from Tuesday night and for the rest of the week, a northerly wind from the Arctic will turn things much cooler, with temperatures nationwide ranging from highs of 1C to 4C, several degrees below the average of 6C to 9C.
“We’re also going to see widespread hard overnight frost with temperatures dropping below freezing, hitting -2C to -6C by the end of the week,” Mr King said.
“For most parts of the UK what we’ll see is sunshine – many more of us will have those cold, crisp, sunny mornings.”
While snow is only forecast in north east Scotland, “the situation is that it will be cold enough for anywhere in the UK to see snow.”
Higher than average temperatures throughout October and much of November, combined with rising energy bills, meant that many people have put off turning the heating on to warm their homes.
However, this could prove dangerous for vulnerable people.
The World Health Organization considers an “adequately warm home” as reaching as 21C in living rooms and 18C in bedrooms – but studies have shown that the average temperature that people will be living in if they can’t afford to heat their homes is only 10C.
What does an unheated room do to your body?
Living in such low temperatures puts a considerable strain on the body, which has to work to warm up faster.
This can lead to an increase in blood pressure and a faster heartbeat – which in turns can exacerbate the risk of a stroke or heart attack.
At low temperatures, those who already have poor heart health and the elderly become even more susceptible to serious health issues.
Prof Damian Bailey, from the University of South Wales, told BBC News “the evidence clearly suggests that cold is more deadly than the heat, there are a higher number of deaths caused through cold snaps than there are through the heat snaps”.
A study published earlier this month suggested exposure to indoor cold not only increases risk of respiratory and circulatory illness but may also harm mental health.
Becoming unable to keep the home adequately warm leads to “statistically significant increases in the odds of reporting severe mental distress” for both those with no mental health problems and those with borderline mental health problems, the study said.
Last year, a report by the Building Research Establishment (BRE) suggested poor housing conditions in England alone cost the NHS £1.4bn – and that half of that sum (£857m) can be attributed to residents’ exposure to cold in their homes.