The River Ouse has burst its banks flooding part of the centre of York as forecasters warn of more heavy rain.
Shops and businesses are flooded
Wales, the Midlands and southern England are set to get the worst of the rain on Monday night and Tuesday.
The Environment Agency has 49 flood warnings in place in England and Wales after heavy rain and the weekend thaw swelled rivers.
In the Midlands alone, there are 27 flood warnings in place. North east and south west England are also at risk.
The heavy rainfall which began on Monday is expected to last throughout the week, although temperatures will be mild.
A PA Weathercentre spokesman said: "Until Wednesday night there's band after band of rain moving through.
"Across the west there will probably be between three and four inches of rain before Wednesday night."
Police are also warning motorists to beware of standing water and flooded roads.
Strong winds died down on Sunday night after causing major disruption over the weekend, but may return in the west.
Torrential rain and winds reaching up to 74mph caused havoc in some areas on Saturday.
Some 20,000 homes in East Anglia were left without power as fallen trees and branches brought down electricity lines.
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Source: Environment Agency
Power firm EDF Energy said the blackout had been almost fully rectified by Sunday night.
The rain and gales also caused road problems on Saturday.
The old Severn bridge on the M48 had to be closed, while the QE2 bridge on the M25 at Dartford was also shut.
In south Wales, a 12-year-old boy died after he and three friends were swept down the swollen River Ebbw near Newport.
Police officers called to the scene pulled him out after one of the boys raised the alarm.
They tried to resuscitate him but he was pronounced dead at hospital later.
Susanne Baker, of the Environment Agency, urged residents to monitor the agency's flood warnings either online or via floodline on 0845 988 1188.