Travellers at Heathrow Airport are experiencing delays and cancellations due to the winter weather. For Heathrow flight information click here.
Heavy snow is expected in parts of Scotland today, with forecasters warning of blizzard conditions and bitterly cold temperatures.
The Met Office issued alerts for central Scotland, Tayside, Fife, Grampian, the Highlands and the Borders, where 4in-8in (10cm-20cm) of snow was expected to fall, accompanied by strong to gale-force winds in some areas.
People should be prepared for the risk of disruption to travel and power supplies as temperatures hover around the freezing mark, forecasters said.
Edmund King, president of the AA, has warned of people driving so-called "snowman cars" by not clearing off the piles of snow on top of their vehicles before getting behind the wheel.
Drivers must clear the snow off their windscreens, lights and tops of their cars before setting out.
This morning we have spotted lots of 'snowman cars', which are cars driving along with piles of snow on their tops.
I saw one sports car this morning on the M3 with almost a snowman of its roof but the dangerous thing was that it was being followed by a motorcycle.
The hardened snow could have been a real hazard, had it fallen off in the path of the motorcycle.
– AA president Edmund King
We have also seen drivers peering out of small openings on their windscreen as if they were driving a tank.
The other issue is the number of cars with their lights and indicators compacted with hardened snow.
Drivers need to take a broom to clear excess snow off their vehicles before setting out.
We have operatives out re-filling salt bins today. We've had several reports of great community spirit over the weekend. Keep it up Cardiff.
@dazrun666 Thanks for helping. We're hoping to refill salt bins today and tomorrow - subject to the weather. Any queries call 0116 305 0001.
Priority 2 routes underway, town centre footways being hand salted. Arranging gangs from a sub contractor to fill salt bins today/tomorrow
Rail commuters are facing delays of up to 60 minutes this morning because of the snow and icy conditions.
Delays of up to 40 minutes between Macclesfield and Stoke-on-Trent because of a signalling problem near #Congleton
Flights have been stopped at Leeds Bradford Airport while snow is cleared from the airport's runway. Delays are expected as a result.
As a result of adverse weather flights are currently not operating at Leeds Bradford Airport for a sort period.... http://t.co/iAXKkgRK
Stansted Airport has tweeted a photograph of its 'snow teams' clearing snow from it's runway.
The tweet adds that the airport is "open and operational".
Commuters face nightmare journeys as a layer of snow and icy conditions prove hazardous in the morning rush.
Virgin Trains warned of some cancellations in its services between London and Birmingham and the North West, while services into London King's Cross were also affected.
Eurostar, First Capital Connect, Southeastern, Southern and South West Trains were all facing disruption.
There were delays on some London Underground lines, mainly because of late finishes to engineering work, while the bad weather caused hold-ups on the London Overground service.
Heavy snowfall closed two major roads across the Pennines, the A628 Woodhead Pass and the A66 between Brough and Bowes.
The Highways Agency said both routes would be closed for some hours and advised drivers to find alternative routes across the Pennines.
At Heathrow, some 10% of flights were expected to be cancelled, particularly after 4pm when visibility is expected to be low.
Passengers were advised to check the status of their flights before travelling to the airport.
Thousands of schools will remain closed today as Britain continues to suffer in the grip of winter.
Students around the country will take an extra day off as schools remain closed in counties to the north and east of London.
In some cases, parents were asked to bring shovels to help clear paths to enable to enable them to open.
A man was killed when the car he was driving left the road in wintry conditions.
The accident happened on the northbound carriageway of the A12 between Kelvedon and Marks Tey in Essex at about 7.05pm on Sunday.
Police found a Ford Mondeo had left the road and crashed into with a tree.
The driver, a 59-year-old man from the Colchester area, died at the scene.
His passenger, a 57-year-old woman, also from the Colchester area, was taken to Colchester General Hospital with serious but not life-threatening injuries.
Witnesses are asked to contact the Essex Police Serious Collision Investigation Unit on 101.