Wintry weather is set to cause widespread disruption across transport routes in England and Wales following significant overnight snowfall and sub-zero temperatures that show little sign of relenting.
Motorists are being warned of treacherous road conditions after more than two inches (6cm) of snow blanketed some regions and the mercury plunged to -4C.
The freezing conditions are expected to continue in the coming days with temperatures plummeting to as low as -9C - bringing an end to a week of Arctic weather that has caused chaos up and down the country.
Last night snow began falling in the North and the Midlands before gradually hitting the Home Counties, East Anglia, London, the South East, the South West and Wales.
Victoria Kettley, forecaster at MeteoGroup, the weather division of the Press Association, said: "The snow began around 6pm before intensifying. The heaviest falls were seen over a band covering South Yorkshire and Leicestershire with accumulations of between 5-6cm.
"As the evening progressed the heaviest snow spread southwards before fizzling out towards Wales and the South West."
She added: "The overnight weather means there will be treacherous conditions on the roads this morning as the snow melts and poses the threat of widespread ice on untreated roads."
A "yellow" severe weather warning instructing people to "be aware" of snow and ice in nearly all parts of England as well as south Wales has been issued by the the Met Office. A level three cold weather alert is also in place.
Ms Kettley said snow could return to the South West and Wales today with the rest of the UK remaining dry but bitterly cold.
"There could be temperatures of between -7C to -9C tonight and over the weekend it will be bitterly cold," she said.
"Air temperatures might not get above freezing across the Midlands and East Anglia throughout Saturday, increasing the danger of ice."
Surrey Police advised people to take care with up to 5cm of snow expected to have fallen by the morning's rush hour.
A force spokesman said: "We are reminding residents and motorists to stay safe and take sensible precautions following further adverse weather conditions in the county. The freezing conditions could lead to some potential disruption on the road network, particularly during the morning rush hour.
"Residents are also reminded to check on elderly of vulnerable neighbours, friend or relatives."
Those travelling to Heathrow Airport have been advised to check their flight's status before setting off and allow extra time for their journey after it was hit by show overnight. However, officials said no disruption is expected.
Gatwick, London Luton, Birmingham International and Stansted said they were open and operating as normal and were not expecting disruption despite the wintry weather.
Yesterday treacherous conditions caused by freezing rain led to more than 100 road incidents in Cumbria alone. The A66 was one of the worse hit routes with cars colliding and skidding off the carriageway.
A spokesman for Cumbria County Council warned that road conditions were expected to remain hazardous, describing yesterday's freezing rain falling on the ground as a "perfect storm".
Meanwhile, classic car enthusiast Tim Waddingham, 53, is thought to have drowned trying to rescue his dog from a freezing pond at a golf club in Surrey the weekend.
North West Ambulance Service said its control centres had answered more than 700 emergency calls yesterday and responded to 187 incidents where patients had fallen.
Charities have warned that elderly people are among the most vulnerable in the freezing conditions.
Age UK director general Michelle Mitchell said more than a third of over-65s fall each year, with snow and ice posing a particular risk.
She said: "Winter can be a dangerous time for older people particularly with the current plummeting temperatures.
"Low temperatures raise blood pressure which puts people at a greater risk of heart attacks and strokes as well as increasing the likelihood and severity of flu and other respiratory problems.
"During this period of cold weather, we would urge people to check on their older relatives or neighbours to ensure they are warm and have plenty of food.
"We would also encourage people to be good neighbours and clear pathways of snow and ice, if they are able to help older people stay safe."
A spokesman for the Association of Train Operating Companies (ATOC) said train companies were gearing up to deal with the bad weather, with Network Rail running empty 'ghost' trains and de-icer units to keep tracks and overhead cables free of snow and ice as far as possible.
He added: "The whole industry will be working hard to get people from A to B as quickly and reliably as possible."
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