Snow continues to grip parts of UK
Snow continues to grip parts of the UK with roads in parts of south Wales and south-west England affected.
In Pembrokeshire, a school bus taking 40 pupils home slid off the road but no-one was hurt. The head teacher said conditions were "probably the worst" he had seen in 25 years.
Hundreds of schools remained closed across the UK, although numbers shut were down on the start of the week.
Forecasters predict milder and wet conditions by the weekend.
In Somerset, gritter crews have had their work cut out after almost 15cm of snow fell in 24 hours.
Somerset County Council said that, to combat icy conditions for motorists, twice the usual amount of salt would be used to treat roads on Wednesday night.
The freezing temperatures across the UK are expected to continue until Saturday.
The Met Office has issued yellow warnings advising people to "be aware" of more snow in parts of Wales, south-west England, north-west England, and eastern and north-eastern Scotland on Wednesday evening.
It says icy surfaces will continue to be a threat across much of the UK, especially where snow has fallen over recent days.
The Environment Agency says rain and melting snow are expected to lead to rising water levels in rivers in south-west England and has three flood warnings in place.
In other developments:
- Fresh snow has caused more road disruption as it spread west across Wales, causing road problems in particular. More than a quarter of schools in Wales - 475 - were closed on Wednesday
- In Scotland, drivers have been warned about ice and snow on the roads in Grampian, Tayside and the Borders after several days of heavy snow. About 70 schools were closed, more than 50 in Aberdeenshire
- More than 90 schools were closed across Somerset, more than 50 were closed in Herefordshire and Worcestershire, and about 40 were shut or partially closed in the West Midlands
- A 42-year-old man died after his Ford Fiesta collided with another car in Plymouth during a hailstorm
- Nuneaton Market in Warwickshire was closed for a second time after several centimetres of snow fell overnight
- Doncaster's horse racing meeting on Friday has been abandoned because of snow on the track
Some flights were cancelled at Heathrow on Wednesday. The airport said it was "fully operational" but acknowledged there might be further disruption due to the conditions in the UK and Europe.
Speaking on BBC Radio 4's Today programme, the airport's chief executive, Colin Matthews, said Heathrow had invested £36m in snow-clearing equipment and was "in no way in the same position as 2010" when a runway closed for nearly four days.
He said two-thirds of flights operated on Monday and nearly 90% on Tuesday.
"I'm really sorry for every passenger who got caught up with the disruption and the cancellations but the fact is when it snows we have to clear the snow off the runway," he said.
"It takes us a little time to clear the snow off and during that time we can land less aircraft and take off less aircraft than in normal conditions and therefore because we are full any amount of snow is going to cause some disruption."