Potential flooding could hit parts of the UK over the coming days as heavy rain sweep across areas of the country, forecasters said.
People in south-west England and Wales have seen deluges of 15-20mm overnight, with the wet weather expected to spread further east during this morning before clearing.
More downpours are expected later tonight though and rainfall readings could reach 30mm by tomorrow, according to weather experts.
A severe weather warning of heavy rain has been issued by the Met Office for Wales, the West Midlands and south-west England.
Issuing the yellow warning, which urges people to be prepared, the national forecaster said: "Periods of heavy rain are likely across the southern half of Wales, south-west England and the south-west Midlands from the beginning of Friday until Saturday morning.
"It is looking increasingly likely that one area of heavy rain will move through during the small hours of Friday followed by a drier interlude, before further heavy, persistent rain moves eastwards later on Friday into the early hours of Saturday.
"However there still remains considerable uncertainty in the details of the heavy rain by late Friday and the warning may be adjusted further as the event approaches.
"The public should be aware of the possibility of disruption to travel due to localised flooding."
Nick Prebble, a forecaster for MeteoGroup, the weather division of the Press Association, said 30mm of rain could hit areas of southern England and Wales.
"It's going to be a wet one," he said.
"The spell of rain from overnight should clear away during the day, but another pulse will move in later brining some heavy bursts."
The Environment Agency currently has 18 flood alerts in place in the south-west, Midlands, Anglian and north-east regions. Three flood warnings in place in the north-east.
Heavy rain began to move in across Devon, Cornwall and southern Wales late last night with up to 20mm falling in places during the early hours, Met Office forecaster Greg Dewhurst said.
The weather expert predicted similar rain falls in tonight's second burst of bad weather.
Mr Dewhurst said southern areas could expect temperatures of 14C (57F) to 15C (59F) over the next few days, with the London area reaching 17C (63F).
Despite seeing spells of dry and sunny weather, northern areas will feel slightly cooler with temperatures between 12C (54F) and 14C (57F), he added.