Widespread disruption as heavy snowfall continues across UK
Unrelenting snowfall has ground parts of Britain to a standstill, trapping motorists on roads overnight and threatening air, rail and road journeys across the country.
Another day of sub-zero temperatures, gale-force icy winds and blizzard-like conditions is expected as Storm Emma sweeps in from the Atlantic on the tail of the Beast from the East's chilly blast.
The Met Office escalated a heavy snow weather warning for south-west England and south Wales to red - its highest level - meaning "widespread damage, travel and power disruption and risk to life is likely" from 3pm.
Scotland has faced the brunt of the extreme weather so far, with police warning the public against travel until a red warning across the south of the country passes at 10am.
Hundreds of motorists on the M80 near Glasgow reported being stuck for up to 13 hours, with some spending the night in their cars, and others abandoning their vehicles on the motorway.
Around 1,000 vehicles were at a standstill, tailing back eight miles in both directions, Police Scotland said.
Major airports including London Gatwick and Heathrow told passengers that cancellations loomed, while Glasgow Airport announced it was closed until 3pm.
Rail services have also been mired by delays with Paddington Station announcing it will be closed from 8am due to severe weather conditions.
More than a foot of snow was dumped in some parts of the country - peaking with 34cm of snow in Wittering, Cambridgeshire.
The Met Office said it had likely been deeper than this in some places, but dry, windy conditions had made it hard to measure.
Temperatures dipped as low as minus 10.3C in Kinloss, Scotland, overnight.
Up to 50cm of snow is expected by tomorrow morning over Dartmoor in Devon.
Hundreds of schools across the country were forced to close for the second day in a row, including more than 125 schools in North Yorkshire, more than 330 across Kent and all schools and colleges in the Republic of Ireland.
Forecaster Greg Dewhurst said: "Through the night the worst hit areas have been over our red warning area in the southern belt of Scotland and Lothian.
"We are looking at a very busy day on Thursday. We are look at heavy snowfall pushing across southern Wales and south-west England through the day but there will be gale-force winds as well, the worst have been blowing to blizzard conditions.
"It will be very windy everywhere and very cold - temperatures will stay below freezing for much of the country."
The UK has not witnessed such a widespread spell of cold since around March 2013, he added.
In Lincolnshire, police warned that "most roads" had become impassable, with the force's control room tweeting that it had received reports of some remote villages being "totally cut off under 2ft of snow".
The A52 was closed between Boston and Skegness all night, with not even a snowplough able to get through, the fire service said.
Suffolk Police "strongly advised" drivers not to travel unless absolutely necessary.
As well as the red alerts - which has never before been issued for Scotland, England or Northern Ireland - amber warnings have also been issued for the north-east of England and the central belt of Scotland, in place between 10am and 6pm on Thursday.
On top of these, yellow snow warnings have been issued for vast swathes of southern, central, and northern England, Northern Ireland and Wales - in place for most of Thursday.