Travel disruption is expected to push into Monday’s morning rush hour, with yellow warnings for ice, fog and snow in place across much of the UK.
The Met Office issued the warnings as temperatures were expected to stay well below freezing overnight and combine with wintry showers to create icy conditions.
Snow on Sunday night forced airports to close runways and left drivers struggling to get through.
The warnings came as four children were taken to hospital in a critical condition after being rescued from a lake in Solihull in the West Midlands on Sunday afternoon after falling through ice.
Richard Stanton, area manager for West Midlands Fire and Rescue Service, said: “We know the weather forecast for the next few days is expected to be bitterly cold. Please, adults and children alike, stay away from open water, under no circumstances go out on the ice no matter how thick or safe you think this ice may be.”
Motorists in the south east were told by National Highways not to travel unless necessary due to heavy snowfall on Sunday evening, with up to 10cm of snow forecast.
Kent was particularly hard hit, with snow affecting the M2, M20 around junctions 8 and 9, the A21 and the A249, the organization said.
Gina Oxley, National Highways duty operations manager for the region, said: “We have been out and about throughout the afternoon and we continue to process routes so we can reach the worst affected areas and support our customers with their journeys.
“For anyone thinking of traveling, our advice would be to refrain from doing so unless absolutely necessary, as heavy snow is expected to continue until [on Monday].”
Airports were also affected, with both Gatwick and Stansted having to close their runways on Sunday to clear snow.
Essex Airport said in a statement: “London Stansted Airport’s runway is currently closed to allow snow clearing due to weather conditions and all flights are currently cancelled.
“Delays to flights were experienced in the past due to de-icing of aircraft, which is the responsibility of a ground handler and the safety of aircraft and passengers is paramount. Passengers are advised to check with their airline for the current status of their flights.”
Gatwick posted on Twitter: “Sunday 11/Monday 12 December: Snow and freezing weather may cause disruption at airport. Passengers are advised to check flight status with their airline – and also local travel conditions – before traveling to the airport.”
National Rail said snow and ice had caused serious disruption across the south-east network on Sunday evening and delays would continue into Monday, “especially in the morning”.
“To allow Network Rail to check that the tracks are free of snow and ice, which could prevent trains from drawing power from the electric rail, the first trains in each direction on all routes will be cancelled,” it said.
“We also have many trains in the wrong location following yesterday’s disruption, which will lead to further cancellations of services across the network.”
Newspaper distribution, including that of the Times and the Sun, experienced significant disruption overnight, which could lead to delivery delays “in many parts of the country”.
News UK said in a statement that severe weather in the south east had affected the printers in Broxbourne, Hertfordshire.
“We apologize to retailers and customers who cannot get a copy of their regular newspaper. Newspaper printers will continue their work delivering newspapers to retailers during Monday, the statement said. “Please follow our websites and apps for news and further updates.”
The yellow warnings were in place from Sunday until Monday morning for north and south-west Scotland, Northern Ireland, north-east England, the Midlands and south-west, as well as London and the south-east.
Met Office meteorologist Rachel Ayers said: “It will continue to be a very cold day, with maximum temperatures of 1C to 4C on Sunday and as we head into the evening we will see persistent rain, sleet or snow in the far south. -east of England, which is what we have a yellow warning out for from 6pm on Sunday.
“We could see 2cm to 5cm (of snow), perhaps up to 10cm in some places, with Kent and Sussex most affected, with most exposed areas such as the North and South Downs and higher ground seeing the more significant accumulations.
“There will be ice forming, especially near the coast where there is rain and sleet, and freezing temperatures that could cause some travel disruption starting Monday with what will be in place until 9am.”
Ayers said that while cold temperatures, freezing fog and wintry showers are expected throughout the week, cloud cover could prevent some of the more extreme temperatures experienced in recent days.
She added that there was a possibility of slightly milder conditions next weekend, but it was too early to be sure.
The AA advised motorists to adapt their driving to the cold conditions on Monday morning.