Millions of Brits are warned to brace themselves as temperatures are set to plummet to minus 10C this week, sending energy bills rocketing.
Frost has hit higher northern areas this morning with snow forecast in some parts of Scotland.
The Met Office and UK Health Security Agency (UKHSA) have issued severe cold weather alerts for England and have advised people to heat their rooms to at least 18 degrees.
A dramatic drop in temperatures could increase health risks to vulnerable people and disrupt deliveries further.
Met Office forecaster Dan Stroud said: “Into Tuesday night an organised band of showers will sink south, (with) that wind changing direction and coming in from the north, turning it colder with an increasing risk of some frost, mainly in central and western areas.
“Once that wind rears around to the north, we’re going to pull in that colder arctic air, so the story will be about cold and frost.”
Amber cold weather alert
A level three (amber) cold weather alert was sent out on Monday warning of severe conditions in England between Wednesday evening and next Monday morning.
Social and healthcare services will be required to respond to protect high-risk groups.
But a cold snap heading over from the Arctic will be spreading into the country from late Wednesday.
Word of warning
Age UK has advised maintaining a supply of food and medicine to reduce the number of outdoor trips and torches with spare batteries in case of a power cut.
Homeless people in London are to be sheltered after the Severe Weather Emergency Protocol (SWEP) was activated for the first time this winter to provide emergency accommodation for rough sleepers.
Dr Agostinho Sousa, consultant in public health medicine at the UK Health Security Agency (UKHSA), said older people and those with heart or lung conditions are particularly at risk from the cold weather, adding: “If you have a pre-existing medical condition, you should heat your home to a temperature that is comfortable for you.
“In rooms you mostly use, such as the living room or bedroom, try to heat them to at least 18C if you can. Keep your bedroom windows closed at night. Wearing several layers of clothing will keep you warmer than one thicker layer.”
On the roads
Select Car Leasing has advised motorists to check their vehicles are winter ready, with properly inflated tyres that have good tread.
Managing director Graham Conway said: “Roads can be much more perilous during the colder months, with snow and ice as well as fallen leaves making the surface slippery for drivers.
“We advise all motorist to carry out regular checks of tyres, brakes and lights to ensure their vehicles are ready for the challenges this cold snap brings with it.”