An area in Northumberland was the coldest location in England overnight as temperatures dropped to almost -10C in the UK.
According to the Met Office , the mercury fell to minus 9.9C (14.2F) in Braemar, North East Scotland, on Monday night.
Nine of the 10 coldest locations overnight were North of the border, but the coldest location in England was Redesdale Camp, in Northumberland , where the temperature was recorded at minus 7.1C (19.2F).
A yellow weather warning for dense and freezing fog was in place across parts of England and eastern Wales on Tuesday morning including Manchester and Birmingham.
During rush-hour, drivers from Brighton to Manchester had to contend with lower visibility and iced-up cars.
According to the Met Office, the freezing fog will "linger" across parts of England and Wales throughout the day.
In the North East, temperatures won't reach more than around 4C on Tuesday and will drop to -1C overnight.
We're set to see widespread frost, strong winds, cloud and fog.
Meteorologist Grahame Madge said: "It's going to clear, but it might be stubborn to clear in some places, and then eager to re-form.
"We have weather warnings out until 11am on Tuesday but in some places it could persist more than that."
The freezing fog hung around throughout Tuesday morning's rush-hour.
North West Motorway Police tweeted to say they had received reports of a "few" accidents, adding: "the gritters have worked tirelessly all night, but it's still icy out there."
They also offered some safety tips for motorists, suggesting people drive on main roads, rather than quieter rural routes, and use a cigarette lighter to warm a key if the locks are frozen.
Mr Madge said: "Fog is always a driving hazard, and people need to take account of that when they are travelling."
He warned drivers not to become complacent if they have passed through a clear area.
Temperatures throughout the day will struggle to reach double figures across much of the country.
Temperatures will fall again overnight on Tuesday, but Mr Madge could not say "whether they will drop to the levels they did last night".
He added: "We have a weather front moving in from the west that's going to stall and bring cloud and rain.
"But for the east the cold conditions are going to persist."
Public Health England has warned people to look out for others who may be vulnerable in the chilly weather.
Consultant Dr Emer O'Connell said: "Older people and those with heart and lung problems are at risk of getting sick in cold weather."
