Heavy snowfall has brought disruption to the roads, rails and skies of the UK.
Severe weather is sweeping across North Wales and central England, with up to 28cm of snow already recorded in parts of the country.
Flights were temporarily suspended at two UK airports – Birmingham and Luton – due to bad weather, causing widespread delays for passengers.
Major roads were also crippled by the weather, with the M1 briefly closed near Leicestershire and the A5 in Shropshire also forced to shut down.
In the West Midlands, an NHS trust was forced to put an appeal out for 4×4 drivers to help stranded nurses get to hospitals.
Heart of England trust, which represents hospitals in Birmingham and Solihull, asked on Twitter: “Do you have a 4×4 and can volunteer to help our nurses get into our hospitals at good hope 424 7564 or heartlands 424 0483 pls give us a call. Thanks”
Good Hope Hospital in Sutton Coldfield serves northern Birmingham, while Heartlands hospital is based in Bordesley Green, in the east of the city.
The trust earlier said online: “Trained nurses needed at goodhope hospital due to heavy snow. If can get in pls call site office 424 7564.”
Up to 10cm is expected to build up quite widely, with 15-20cm in some spots, raising the prospect of roads becoming impassable.
The amber alert is accompanied by a yellow warning of wind for parts of eastern England, London and the South East, the South West and Wales that could bring “short-term loss of power and other services” as well as transport disruption.
London and the rest of southern England and Wales will instead be lashed by strong winds and rain, where gusts could reach 70mph, according to the Met Office.
Londoners also unexpectedly woke up to snowfall, as forecasters initially predicted the capital and southern England and Wales would instead be lashed by strong winds and rain.
Rail routes into London were disrupted by the snow, including Great Northern, London Overground, Thameslink, Virgin Trains East Coast and Transport for London Rail services.
In the Midlands, rail passengers were advised by National Rail “not to travel this Sunday”, as disruption hit Cross Country, London Northwestern Trains, Virgin Trains and West Midlands Railways services.
The Met Office issued an updated amber warning lasting from just after 8am to 6pm on Sunday, covering parts of Wales, the Midlands and areas of northern and eastern England.
The heaviest snowfall was found in Sennybridge, south Wales, where 28cm of snow was recorded, the forecaster said.
The amber alert is accompanied by a yellow warning of wind for parts of eastern England, London and the South East, the South West and Wales that could bring “short-term loss of power and other services” as well as transport disruption.
Met Office forecaster Steven Keate said: “The worst of the snow is currently across parts of Wales and the west and southern Midlands, while there is some snow falling over the home counties as well.
“Herefordshire, Shropshire and Powys have seen a few centimetres in a couple of hours.
“Steady snow is expected as this weather system moves over the next few hours into the afternoon roughly from mid-Wales to the north of London.
“There’s going to be a split from the M4 corridor south, where it will mostly be rain, although the winds are really picking up there as well with gusts up to 60mph in some places in the south.
“North of the Humber should get away with it today, although there may be showers in the far north of Scotland.
Luton Airport shut down its runway for around an hour on Sunday morning, temporarily suspending all flights just after 10am.
It reopened the strip for departures only at 11.30am, writing online: “For the latest status of your flight please check with your airline.
“Passengers are advised to leave additional time for your journey to the airport. We apologise for any inconvenience.”
Flights were also grounded in Birmingham Airport while the runway was cleared.
Highways England advised motorists to avoid the roads in affected areas, urging them to ensure they pack first aid kits, shovels, food, drink, warm clothing and blankets before setting out.