Fresh flood warnings were issued on Monday as further heavy rain and strong winds due to batter Britain this week bring a new risk of danger and disruption.
Devon, Somerset and south east Wales are likely to be the worst hit by the new downpours, the Environment Agency said, with strong winds meaning coastal defences could be overrun.
The UK has already been battered by winds of up to 60mph on Monday and they could be whipped up to 85mph by Tuesday night, according to Meteogroup, the weather division of the Press Association.
Mobile flood barriers are being erected in Bewdley in Worcestershire and Shrewsbury in Shropshire in preparation for large rivers, including the Severn and the Wye, rising to flood levels during the week.
"Communities in the south west of England and south east Wales are being urged to prepare for more flooding this week as further rain fall is likely to cause flooding and significant disruption," an Agency spokeswoman said.
"Devon, Somerset and south east Wales are most likely to be affected, and strong winds could lead to some disruption along the coast as waves and spray come over the top of defences."
A deep Atlantic storm is one of a series of weather systems heading to the UK, Meteogroup said, bringing fresh rain falling on ground saturated by recent downpours and the thaw from last week's snow.
The Environment Agency says it is closely monitoring weather forecasts for the next few days. There are currently 62 flood alerts in place across the south-east of England, with over an inch of rain expected in Kent and South London on Tuesday. Oxfordshire, Berkshire, Hampshire and Sussex will see rainfall increasing as the week goes on, with the heaviest rain expected to fall on Friday.
According to the Agency, many rivers remain above their usual winter levels following recent snow and rainfall, and ground is already saturated. Residents should be prepared for further flood alerts and possible flood warnings, particularly across Hampshire and into Berkshire.
Alison Baptiste, Environment Agency Flood and Coastal Risk Manager, said: "It looks like it's going to be a wet week, with heavy rain forecast across the region for the next five days.
"Our teams are working hard to prepare and to make sure our professional partners are prepared. We have officers out checking flood defences and clearing any river blockages. We are receiving regular updates from the Met Office, and will continuously monitor river levels.
"Now is a good time for anyone who lives in an area vulnerable to flooding to think about the precautions they can take to protect their properties, and I would encourage everybody to check their flood risk at the Environment Agency website and keep up to date on warnings."