Flooding possible for South Wales with another yellow weather warning
The latest Met Office alert comes into force at 4pm on Sunday.
The UK is braced for heavy rain and strong winds just days after homes and businesses were flooded.
Two fresh weather warnings come into force on Sunday for wind and rain which will hit areas already saturated by downpours earlier in the week - including South Wales.
A yellow rain warning has been issued by the Met Office - meaning further heavy rain is likely to cause some travel delays and flooding - covering much of southern England and South Wales between 4pm on Sunday and 9am on Monday.
Between 20mm and 30mm of rain could be seen within the warning area across nine to 12 hours on Sunday, and 50mm to 80mm could fall in some localised places on higher ground, the Met Office said.
Met Office meteorologist Becky Mitchell said it was "not a huge amount of rain" but because of the recent weather "river levels are quite high and grounds are quite saturated", so more flooding could develop.
Meanwhile, a yellow warning for wind is also predicted to cause disruption across south-west England and Wales between 9am on Sunday until the end of the day.
Gusts of between 50mph and 60mph could be seen, with large waves, trees brought down, travel disruption and some power cuts, Miss Mitchell said.
There could potentially be further rain warnings issued for Monday, but it is forecast to be drier later in the week, she added.
The Met Office said temperatures on Sunday will be 3C-4C below average, in the low double figures.
Craig Snell, Met Office meteorologist, advised people travelling on Sunday to plan ahead.
He said: "Check rail conditions before setting off, check buses are running on time, and allow extra time for your journeys. If you're driving allow extra braking distances.
"For the areas affected under the yellow rain warning, if you are concerned about flooding, for people in England the main advice is to check the Environment Agency website or Floodline, if you live in Wales it will be Natural Resources Wales."
It comes after areas across England suffered heavy rain and localised flooding in recent days, with commuters facing widespread disruption on road and rail services.
According to the Met Office, some counties in southern and central England have already had more than 250% of their average September rainfall.
Parts of the country had more than the monthly average rainfall on Monday and there were further downpours on Wednesday, Thursday and Friday.