Torrential rain brought by Storm Dennis over the weekend has left more than 300 flood warnings in place across the UK, including five severe warnings in the west Midlands.
The National Rail network has said some routes will be closed for hours on Monday due to flooding.
This includes disruptions between Three Bridges and Brighton until 7am, Southampton Central and Bournemouth until 9am and from Glasgow Central via Cathcart until 10am.
The continuing danger comes after a minister admitted the Government would not be able to protect every house from flooding after the country was hit by a second major storm within a week.
New Environment Secretary George Eustice told Sky News that the Government had not been caught off guard by the floods caused by Storm Dennis.
Speaking during a visit to York to discuss tackling flooding, Mr Eustice said there was always more that could be done.
“We’ve done a huge amount – we can’t do anything about these extreme weather events but the steps we’ve taken have meant the impact of those weather events have affected fewer properties,” Mr Eustice said.
He blamed the “nature of climate change” for the scale of the damage, and said: “There is always more that can be done.
“We’ll never be able to protect every single household just because of the nature of climate change and the fact that these weather events are becoming more extreme, but we’ve done everything that we can do with a significant sum of money, and there’s more to come.”
The Environment Secretary’s comments came after the country took a battering of heavy rain and strong winds as Storm Dennis lashed the UK, just a week after Storm Ciara.
Parts of the UK were buffeted with winds of more than 90mph, while more than a month’s worth of rain fell in 48 hours in some places.
Roads and railways were flooded on Sunday after torrential downpours and high winds.
The Ministry of Defence deployed Army personnel to assist people in West Yorkshire areas badly hit by flooding during Storm Ciara.
The situation was said to be “life-threatening” in South Wales, where the Met Office issued a red warning due to heavy rainfall and flooding risk.
The Environment Agency’s flood and coastal risk management executive director John Curtin said there had been a record number of flood warnings and alerts in force.
The Government was criticised for its response, including a Tory MP telling it to “pull its finger out”.
Conservative MP Philip Davies told the Daily Telegraph on Monday that “precious little” had been done since the floods in 2015 to prevent his constituents in Shipley, West Yorkshire, being flooded again during the two most recent storms.
“My constituents who were flooded were the same people who were flooded on Boxing Day 2015,” he told the paper.
“It’s not as if there hasn’t been enough time to do something. The Government needs to pull its finger out.
“What has been done to stop it happening again? Precious little.”
The Met Office said winds exceeding 80mph were recorded across parts of the country over the weekend, with the highest measuring 91mph in Aberdaron in North Wales on Saturday.
A total of 156.2mm of rain fell at Crai Reservoir in Powys in the 48 hours from Friday to Sunday morning, it added.
The average monthly rainfall for February in Wales is 111.1mm, the Met Office added.
A yellow weather warning for wind is in place until 11am on Monday.
Pictures on social media showed the River Taff bursting its banks and flooding parts of Pontypridd, while rescue workers used boats to take families to safety after further flooding in nearby Nantgarw.
South Wales Police declared a major incident due to the flooding and severe weather.
Shropshire Fire and Rescue Service told the PA news agency a water rescue unit had been rushing to a report of two people being swept away in the River Teme when it was submerged in flood water.
A spokesman said the crew were safe and had been pulled to safety but the vehicle was still to be recovered.