Despite weather forecasters predicting an "improving picture" with lighter winds and less rain, the Environment Agency said parts of southern, south-west and central England remain at risk of more flooding due to high river levels following the recent heavy rainfall.
Industry body the Energy Networks Association said "relentless" severe weather had caused some of the worst damage in decades, with more than 65,000 homes still without power last night, while 600,000 customers had been reconnected since the Friday night storms.
Meanwhile, 16 severe flood warnings - meaning there is a danger to life - were in place yesterday, along with 150 less serious flood warnings and 250 flood alerts across England and Wales.
Prime Minister David Cameron chaired a meeting of the government's emergency committee, Cobra, last night to discuss the impact of the weather over the coming days. And the Environment Agency said it had closed the Thames Barrier in London for a record 16th consecutive tide to help lower river levels.
One victim of the storms was a minicab driver who died when part of a building collapsed on to a car in central London.
Mother-of-three Julie Sillitoe, 49, was killed close to Holborn Underground station after large chunks of masonry fell on to her silver Skoda Octavia car.
Her passengers, a 25-year-old man and a 24-year-old woman, are currently being treated in hospital.
An 85-year-old cruise ship passenger also died after 80mph winds whipped up freak waves in the English Channel. He was aboard the 22,000-tonne Marco Polo cruise ship when water crashed through a window, injuring a number of people.
The man was airlifted off the vessel along with a woman in her 70s, but he later died. About 10 other people suffered minor injuries and were treated on board.
Meanwhile, on Friday night, more than 30 people had to be rescued from a seafront restaurant in Milford-on-Sea, Hampshire, after wind-blown shingle shattered windows and the sea flooded it.
A 20ft deep sink hole also appeared yesterday morning in a cul-de-sac in Hemel Hempstead, Hertfordshire.
Some 17 homes close to the site were evacuated as the hole, measuring about 35ft wide and 20ft deep, was investigated.
Yellow "be aware" weather warnings of icy driving conditions are now in place for most of the UK. Across the south of England, Wales and the Midlands there are also warnings of heavy rain.
There is already major disruption across Britain's road and rail networks, with flooding and hundreds of fallen trees blocking roads and rail tracks and damaging overhead lines.
Winds wrought fresh havoc, with gusts of up to 80mph hitting exposed parts of the south coast, while waves of up to 33ft threatened to cut off Portland in Dorset.
Communities have been using sandbags and makeshift barriers to protect homes and businesses from the floodwater, while emergency services and army personnel battle the effects of the weather.
In Chertsey, servicemen and women have been helping place a 600m Aquadam flood barrier brought over from Sweden.
The RAF has flown its Tornado GR4 and Sentinel aircraft to capture images of the floods which are being used to co-ordinate efforts to prevent further flooding.