Parts of Scotland have been issued with a red alert weather warning from the Met Office.
Major disruption is expected in Strathclyde, Lothian, Tayside, Fife and Central regions, as well as south west Scotland and the Borders.
This is the first time that the severe weather warning has ever been issued in Scotland, and covers the times between 3pm today (Wednesday) and 10am on Thursday.
The Met Office are warning that roads will become blocked by deep snow, there will be long delays and cancellations to bus, rail and air travel and some communities could be cut off for days.
There is also expected to be long interruptions to power supplies and other services.
The warning comes after Yorkshire’s own weather warning was upgraded from yellow to amber in some parts, including Sheffield and Scarborough.
Police in Newcastle have said power has been restored to about 500 homes and that the outage is no longer being treated as a major incident.
An underground electrical fire at about 3.20pm in Ponteland Road, Cowgate, prompted Northumbria Police to launch an operation to ensure a “large number” residents left without power were safe amid the freezing weather.
The force tweeted shortly after 1am: “Electricity has been restored to all affected homes in Cowgate - it is no longer being treated as a major incident.”
Superintendent George Maratty thanked Morrisons, which provided a reception centre at a local supermarket, and the Red Cross for their support.
Several roads across the country have been closed due to the severe weather.
Part of the A1 in Cambridgeshire is shut in both directions, between the A1M junction 17 and the A6121 at Tinwell.
Cambridgeshire Police said traffic was at a standstill on both the north and southbound carriageways between Stamford and Wansford.
A snowplough has been deployed under police escort to help get traffic moving.
Highways England said the A66 had also been closed in Durham, between the A1M and the A685, while the A59 in North Yorkshire was closed westbound after the A61 between Harrogate and Skipton.
Glasgow City Council has closed all schools and nurseries for the day due to the weather, while West Lothian Council has closed all schools.
Renfrewshire Council said that all its schools and nurseries would be shut due to the severe weather overnight.
In Aberdeenshire more than 120 schools are shut.
A ski centre has been forced to close because of the heavy snow.
Chatham Ski and Snowboard Centre in Gillingham, Kent, shut on Wednesday “due to weather conditions”.
It said on its Facebook page: “Centre currently closed as we have an inaccessible car park and we have to be able to have emergency vehicle access and staff are struggling to get to site.”
Network Rail South East tweeted: “Our teams have been out all night but despite their efforts we do have some problems this morning. Please check before you travel today.”
Virgin Trains said the route between Carlisle and Scotland is closed with no trains or replacement buses running, because of the weather.
Alternative rail routes between England and Scotland are also “severely disrupted”.
A spokesman said: “We will let customers know if Network Rail can reopen the route, but customers should assume there will be severe disruption for the rest of today.
“Customers who wish to postpone their journeys and travel tomorrow can do so - tickets will be valid. Alternatively, if customers would prefer to cancel their journey, refunds will be given without any fee being charged.”
Wind whipping off the North Sea blew down lamp posts and one hit a moving car in Whitley Bay, North Tyneside.
Northumbria Police said no-one was injured when it hit the passenger side of the car.
Press Association photographer Owen Humphreys was at the scene and said: “I have been out in a lot of severe weather and this is some of the worst I have seen.
“There’s been blizzards, thunder, lightning and now wind blowing down lamp posts. The wind really is driving in off the North Sea.”
He captured video of a lamp post shaking violently as a blizzard blew through.
North Tyneside Council said the lighting providers SSE will switch off the electricity and remove the four fallen lamp posts
Cumbria Police said a large number of roads have been affected by the heavy snowfall and urged motorists to avoid travelling if possible.
Supt Justin Bibby said: “The county’s road network has been severely affected by the weather conditions and will remain so with further snow forecast.
“Emergency services are working together to deliver a co-ordinated response to the adverse weather conditions.
“Our advice is simple. Please consider whether your journey is essential. If not, then take the safe option and avoid travelling until the weather conditions improve.”
Glasgow Airport said in a tweet: “Due to the continued and extreme weather conditions we have had to extend the suspension of all services until 1pm.
“We will continue to provide regular updates via our social channels and website. Please contact your airline for specific flight info before travelling to airport.”
Schools across the UK have been closed by the heavy snow.
Some of the affected areas include:
* Kent, 529
* North Yorkshire, 244
* Suffolk, 370
* East Sussex, 49
* Stockton-on-Tees, 41
* Doncaster, 40
* Middlesbrough, 38
* Hartlepool, 35
The Met Office has issued its highest level of alert for parts of Scotland - a red warning - which means extreme weather is expected between 3pm on Wednesday and 10am on Thursday.
It said: “Heavy snow showers and drifting of lying snow in the strong easterly winds will become more widespread across the area later on Wednesday afternoon, through the evening and overnight into Thursday. Roads will become blocked by deep snow, with many stranded vehicles and passengers. Long delays and cancellations on bus, rail and air travel are expected. Some communities could become cut off for several days. Long interruptions to power supplies and other services.”
The Met Office definition of a red warning is that “you should take action now to keep yourself and others safe from the impact of the weather. Widespread damage, travel and power disruption and risk to life is likely. You must avoid dangerous areas and follow the advice of the emergency services and local authorities”.
After weather officials issued a red alert for parts of the country, Ireland’s Taoiseach Leo Varadkar tweeted: “We are facing an extraordinary weather event. I have instructed all of the machinery of the State to work together to keep people safe. Be prepared in your homes, look out for vulnerable neighbours & avoid unneccesary travel in red areas. Updates at http://gov.ie.”