Some 500 soldiers have been drafted in to help deal with the crisis, with 1,000 more on standby
David Cameron is likely to face tough questions later as he visits communities affected by unprecedented flooding in the north of England.
Thousands of people have been affected as river levels keep rising in York - where entire streets have been submerged.
The British prime minister has promised to "help people in their hour of need" and some 500 soldiers have been drafted in to help.
One thousand more are on standby to help in Leeds, Greater Manchester and swathes of Yorkshire and Lancashire which are also affected.
The UK's environment agency has 24 severe flood warnings in place for the north east and three severe flood warnings in place for the north west, meaning there is a danger to life.
There are almost 200 other flood warnings and alerts in place across the area and other parts including Wales and the English midlands.
The worst-hit areas will have some respite from rain, but the crisis looks set to continue as more bad weather sweeps in.
On Sunday officials made the decision to lift York's flood barrier after water entered a barrier building, causing flooding to around 500 properties.
Families were forced to flee from their homes as residential streets were turned into rivers of mud as waters reached record levels.
Residents affected by the deluge said it had been "frightening".
Engineers have been examining how to restore power to the barrier building while troops spent Sunday stacking sandbags, until they ran out, forcing the council to beg neighbouring authorities for help.
Thousands of homes in northern England have been left without power, with almost 6,000 hoping to be reconnected today.
Teams from insurance companies have been on the ground in the affected areas. Customers have been advised to get their claims started as soon as possible and to take photos of damaged items.
The floods also affected transport links.
West Yorkshire Police declared a major incident after responding to what it said was the "worst flooding in 70 years" in the area.
Judith Blake, the leader of Leeds City Council, said the authority had warned the government that flooding in Leeds was a "catastrophe waiting to happen".
She called for "significant investment" in additional flood defences for the city to prevent future flooding.
News of the flooding has even reached space, where British astronaut Tim Peake passed over the UK on Sunday in the International Space Station.
Passed over UK today - thoughts are with all those affected by flooding in northern England. pic.twitter.com/O2hWL6fCfy— Tim Peake (@astro_timpeake) December 27, 2015