More than 44,000 homes and businesses in Northern Ireland have been left without power after much of the United Kingdom was battered by snow, sleet and storm force winds overnight.
More disruption is expected throughout Friday and emergency services are already responding to a surge in weather-related call-outs with government agencies issuing a string of warnings urging the public to take care on the roads.
The weather has been so severe in the north of England that the Sellafield nuclear power station in Cumbria has been shut down.
The damage to Northern Ireland's power network was concentrated in south and eastern areas, and also parts of the North Coast, operator Northern Ireland Electricity (NIE) said.
George Best Belfast City Airport has reopened its runway after being earlier forced to close due to the weather, while flights at Belfast International Airport have also been disrupted.
More than 70 schools in the region have been forced to shut for the day while commuters have faced hazardous conditions on the roads with snow drifts of up to 15.7in (40cm) reported.
Northern Ireland's World Cup football qualifying fixture against Russia has been postponed until Saturday afternoon with the agreement of both teams' governing bodies.
Ground staff worked throughout throughout the day in a bid to clear the pitch, but with the snow continuing to fall and the forecast remaining bleak, officials were left with little alternative but to reschedule Friday evening's match until 3pm on Saturday.
Staff at Sellafield were sent home from the reprocessing and waste storage facility but the site's operators said there were no safety issues, AFP reported.
A statement from the plant said: "In response to the current and predicted adverse weather conditions on and round the Sellafield site, as a precaution, a site incident has been declared and the plants have been moved safely to a controlled, shut down state.
"There is no reason to believe that there will be any off-site nuclear, environmental or conventional safety issues associated with the incident."
Elsewhere, more flooding is expected in the south-west as Thursday's heavy rain continues to pour throughout the day and overnight.
Snow is expected to blanket everywhere north of the M4 corridor, with up to eight inches hitting the worst affected areas of north-west of England, North Wales and south-west of Scotland.
Higher areas could even see up to 16 inches fall, while bitterly cold gale force winds will sweep across Britain creating blizzard-like conditions and plunging temperatures down to well below freezing.
Heavy rain sweeping across Northern Ireland will turn increasingly to snow with up to 12 inches across the hills of Down and Antrim, while on the east coast rain and sleet could cause localised flooding.
James Wilby, a forecaster for Meteogroup, the weather division of the Press Association, said: "It is really just nasty conditions across most of the UK.
"The snow will fall from the M4 northwards, quite lightly in the south but heavily in the north.
"Along with the heavy rain and flooding in the south-west, there will no doubt be a lot of disruption for the UK.
"The heavy rain, snow and strong winds will continue into the weekend, with the heavy snow spreading south to East Anglia and Bristol tomorrow.
"And I'm sorry to say that there is no sign of things getting any better next week, it's going to remain cold and bleak."
The Met Office has issued a number of severe weather warnings urging the public to be prepared for "severe disruption" to transport and energy services.
The Environment Agency has 18 flood alerts in place along the south-west coast warning of expected flooding, with a further 80 alerts issued to areas at risk.
Between 1.6 to 2.4 inches is set to fall over southern Devon and Cornwall today, and up to 4 inches on exposed southern slopes.
Last night Cornwall Council set up a designated control room to handle calls.
Spokesman Dave Owens said the county's fire and rescue service received more 50 calls, and eight properties had flooded.
He said: "The main problem still appears to be surface water flooding which is continuing to affect a number of areas across Cornwall."
There are reports of flooding across the west of the county, including around Newlyn and Penzance, as well as in Mevagissey in mid-Cornwall - a community still recovering from the impact of last year's torrential downpours.
Environment Agency spokesman Ben Johnstone said: "We strongly urge people to sign up to flood warnings on the Environment Agency website, keep a close eye on local weather forecasts and be prepared for possible flooding.
"We also ask that people stay safe and not try to wade or drive through any deep water."
Leeds Bradford International Airport has suspended all flights due to "adverse weather conditions".
The airport has told passengers: "We advise you contact your airline or tour operator and check the status of your flight before arriving at the airport."
The AA issued warnings to motorists that even short journeys could be difficult, and there could be a repeat of the scenes in southern England last week when hundreds of drivers were stranded in their cars overnight.
Darron Burness, the AA's head of special operations, said: "It's going to be a real witch's brew of driving wind, rain and snow, which will inevitably cause disruption on the roads.
"Drivers should be well prepared as even short journeys can quickly turn bad."
He warned of localised flooding, and urged drivers to stay out of flood water. He also said snow that settles could persist in the low temperatures, leading to icy patches.
"Wherever you're going, take plenty of warm layers, check the travel reports before heading out and stick to the main roads where possible," he said.
The Local Government Association said council gritting and ploughing teams would be out in force to try to ensure main roads remained passable where snow and freezing temperatures had been forecast.
Peter Box, chairman of the Local Government Association's economy and transport board, said hundreds of thousands of tonnes of salt had been spread this winter, but hundreds of thousands more tonnes were available in council depots and new deliveries were coming in.
And he said: "Council staff will be out and about over the next few days checking in on the people they know to be vulnerable and delivering hot meals and portable heaters, collecting prescriptions, defrosting pipes, fixing frozen boilers and making sure they have what they need."
But he also urged residents with elderly or vulnerable family or neighbours to check in on them to make sure they were coping with the latest freeze.
Sales of electric blankets at John Lewis have rocketed during this cold spell.
Chloe Harris, buyer for small electricals at John Lewis comments: “Not many of our customers have been able to escape the freezing temperatures and we have seen a 52 per cent rise in sales of electric blankets based on the same period last year.
"As consumers energy prices rise and temperatures drop, electric blankets are increasingly being seen as a good investment for people wanting that bit of extra warmth without heating the entire house.”