The Environment Agency issues more than 30 flood alerts across the UK after heavy rain lashed the country over the weekend, with high waters forcing the evacuation of 1,000 people across Wales.
The Environment Agency has issued alerts warning of possible flooding in 31 areas – 21 in south east England, three in Wales and others in the Midlands and parts of northern England.
The Met Office warned of heavy rain in London and south and east England.
On Saturday about 1,000 people were moved to safety from flooding in mid Wales, with an estimated 150 rescued.
Forecasters said rain would affect many southern, central and south-eastern parts of England overnight and become persistent and very heavy in places, particularly in the south east.
It said further outbreaks of rain would affect parts of Scotland.
The flood alerts only mean that floods are possible and there are no flood warnings, where floods are likely, in place at the moment.
In West Sussex, about 40 properties as well as the basement of Worthing Hospital were flooded. Most of the water had been pumped out of the basement by Monday morning.
The latest warnings follows a weekend of heavy rain and flooding, mainly focused on Wales.
However, flash flooding also caused the closure of the M1 in West Yorkshire on Sunday night, although the sections affected later reopened.
At the height of the flooding in mid Wales on Saturday about 1,000 people were moved to safety, many of them from caravan parks, as flood waters swept in.
Householders started to return to properties to survey the damage on Sunday, although they have been warned to be careful when returning to their homes.
Elsewhere on Sunday, villagers at Pennal, Gwynedd, were evacuated because of the risk of flooding from a reservoir, after a slight breach in its dam, before being told it was safe to return.
Police said a controlled release of water from a disused quarry had eased pressure on a wall.