Public Health England has urged people to check on the elderly and vulnerable as heavy snow and icy conditions are predicted across the UK over the first February weekend.
The Met Office issued amber weather warnings in the east of England for Sunday – stretching from Norwich down to Canterbury – and warned that hazardous conditions could last well into next week.
The RAC said it expected a sharp increase in breakdowns over the weekend and that people should think “extremely carefully” before setting out on journeys.
Dr Owen Landeg, group leader, of extreme events and health protection at PHE, said it was “crucial” that people check in with relatives and neighbours.
“Cold weather isn’t just uncomfortable, it can have a serious impact on health,” he said.
“For older people and those with heart and lung problems, it can increase the risks of heart attacks, strokes and chest infections.
“So it’s really crucial at this time, especially ahead of a very cold snap, to remember to check on frail or older neighbours or relatives, especially those living alone or who have serious illnesses.
“Make a call or socially-distanced doorstep visit if they live close by, to remind them of some simple but important health tips.
“It’s also helpful to check they have enough food and drinks and any medicines they need. This will help them to stay warm and stay well.”
The Met Office also extended its yellow warnings for snow and ice, covering the length of Britain, from midday on Saturday to midday on Wednesday.
Simon Partridge, meteorologist for the Met Office, added that continuous snow showers and strong wind in the east on Sunday would result in “really bad” visibility and up to 20cm of snow in some areas.
“As the snow is blowing around obviously there may be places where it will accumulate more because it will drift,” he said.
“That means significant disruption and obviously at the moment with vaccination centres open seven days a week that can have a knock-on effect there as well.”
Residents in Kent were told by the council to follow “basic, common sense advice to help keep themselves warm and well”.
Kent County Council deputy director for public health Allison Duggal said: “It is vital that during this prolonged period of severe weather, people act to keep themselves and their home warm – even if this is just by heating the bedroom and living room.”
It comes after drivers were left stranded in two-metre snow drifts in northern Scotland on Friday, and amber warnings remain in place there until midday on Saturday.
Around 22 vehicles were stranded in snow at Loch Droma, north-west of Inverness, and emergency services have been assisting a rescue operation, Highland Council said.
Network Rail said services have been disrupted on the Highland Mainline despite plough trains being used to clear snow.
Ben Aldous, RAC patrol of the year, said: “We are expecting next week’s protracted period of sub-zero temperatures to lead to a sharp rise in the number of breakdowns and ‘bumps’ as those who have to drive struggle with very hazardous conditions.
“As patrols, we are well equipped to deal with the severe cold, but we urge drivers to think extremely carefully before setting out and question whether their journey is absolutely necessary.
“For anyone who has to drive, we’d strongly advise making sure their vehicle is ready for the cold.”
Mr Partridge added that by Monday average daytime temperatures across the country would remain between 1C and 4C.
The lowest temperature recorded overnight on Thursday was minus 0.3C in both Loch Glascaroch in northern Scotland and Shawbury in Shropshire.
There are currently 36 flood warnings in place across parts of England, along the River Severn and the River Thames, put in place by the Environment Agency.
In Maidenhead, parts of Cookham were left submerged after heavy rains caused flooding at Widbrook Common.
Residents living by the Jubilee River previously expressed concern over the efficacy of the local flood relief system and fear that prolonged wet weather could lead to a repeat of 2014, which saw properties flooded twice in the space of two months.