Flood warnings have been handed down after temperatures leapt by double figures in the space of just a few days.
Parts of the UK were 20 degrees warmer on Monday than they were during last week's cold spell in an extraordinary weather shift that saw some left without water due to thawing pipes.
Around 15,000 homes in Sussex and Kent were affected by water shortages after a huge increase in reports of leaks and bursts was reported.
Now, people living in areas of the south and south west coast have been told to prepare for flooding as heavy downpours are forecast on Tuesday.
The Environment Agency has issued 19 'act now' flood warnings for the region, meaning flooding is expected. Residents have been advised to move family and pets to safety and vehicles to higher elevations if is safe to do so.
A total of 73 less severe flood alerts are also in place, with a Met Office yellow warning for rain also in place across a large part of the south coast of England.
Met Office meteorologist Alex Burkill meanwhile predicted temperatures would dip slightly on Tuesday following an exceptionally mild Monday, though would remain far above the recent cold spell.
He said: "Monday night into Tuesday, for most it's going to be a lot milder than it has been of late but we could still see a touch of frost particularly in parts of Scotland.
"I think we're still looking at highs of 12C perhaps 13C towards the south coast but away from that as you head to more central parts and further north we're going to be in mid to high single figures at best, so quite a drop compared to Monday.
"The cold period lasted so long and was so extreme, that's come to an end."
UK weather:
Rain clearing from southeast, then dry and bright for most.
Today:
Rain clearing from southeast, and any fog patches clearing from central areas by late morning. Then dry with sunny spells, although a few showers in the west, heavier and prolonged in the far northwest along with strong and gusty winds.
Tonight:
Clear spells in east allowing a patchy frost and perhaps a few fog patches. Windy elsewhere with showers in the northwest, heavy at times, spreading to other western parts later.
Wednesday:
Band of rain clearing southeast during the morning with any mist and fog patches clearing elsewhere. Many areas dry with some sunshine. Windy with further showers across northwest UK
Outlook for Thursday to Saturday:
Showers or longer spells of rain for most. Breezy, with gales for some southern coasts and hills. Mild generally, though becoming colder across the far north with snow showers.
