In Norfolk, 9,000 homes are being evacuated as local officials attempt to stem the damage from the coastal surge.
A further 1,000 properties are to be evacuated in affected areas in Suffolk and some residents in Jaywick, near Clacton-on-Sea in Essex, are also being urged to leave their homes.
Local officials are setting up emergency accommodation facilities and handing out sandbags to help people protect their homes, police said.
A spokesman said in some areas sea levels could be higher than those during the devastating floods of 1953 - which battered the east coast of England and claimed the lives of hundreds of people.
Defences built since then - including the Thames and Hull barriers - mean that many parts of the country are much better protected, he said. However, some coastal flood defences could be "overtopped" by the combined effect of high tides, high winds and a large tidal surge, he said.
Across the country tens of thousands of properties have been hit by power cuts as winds of up to 140mph battered powerlines.
The Met Office said there had been severe gales of between 60mph and 80mph across Scotland and northern parts of England, and some mountainous regions in Aberdeenshire and Inverness-shire reported speeds of around 140mph.
It has also issued national severe weather warnings for strong winds.
The adverse weather has also caused chaos to the rail network. A number of flights have also been disrupted by the bad weather.
And closures, fallen trees, minor accidents and incidents of flash flooding are affecting the road network in parts of the country.
Environment Secretary Owen Paterson chaired a meeting of the Government's emergency Cobra committee this morning to discuss the response to the storm.
"The purpose of the meeting was to make sure that all of the preparations - which we have well in advance - will work together to benefit the public," he told BBC News.
"I would urge everybody to pay close attention to announcements by the Environment Agency, the Department for Transport and local government.
"In some areas of Norfolk, where evacuations have commenced, I would urge everybody to work closely and to cooperate with the local authorities."
People are being urged to check the Environment Agency website.