Britain should be celebrating the start of spring but the kingdom was shivering Friday after heavy snowfall left tens of thousands of homes without power.
BBC weather forecasters said some 20 to 40 centimetres (eight to 16 inches) of snow would fall in the worst-affected areas.
Northern Ireland bore the brunt of the cold snap, caused by an area of low pressure moving eastwards off the Atlantic Ocean.
"Over 40,000 customers have lost electricity supplies following the storm force winds (up to 55 miles [88 kilometres] per hour), accompanied by heavy snow which caused damage to the electricity network," supplier Northern Ireland Electricity said.
"Damage has been caused by flying debris and high winds, including broken electricity lines and damage to poles and other equipment."
The snow forced the closure of George Best Belfast City Airport, though the larger Belfast International remains open.
Northern Ireland's football World Cup qualifier with Russia, scheduled for 1945 GMT, was in doubt.
The pitch at Windsor Park in Belfast is covered in snow, with more expected throughout the day.
More than 1,000 schools around Britain have been shut, while areas of towns in Cornwall, southwest England, have witnessed flooding following torrential rain.
Temperatures in central London were yet to top three degrees Celsius (38 degrees Fahrenheit) on Friday.
A spell of bad weather this month has seen British media dub it 'Miserable March'.
Will Lang, chief forecaster at the Met Office national weather service, said: "While it is not unusual to see snow in March, the cold weather we have seen has been quite prolonged."
Conditions were forecast to improve over the weekend.