A “potential risk to life and property” warning has been issued in Scotland, with torrential rain expected for yet another day.
The Met Office alert was for an area including East Lothian and parts of Edinburgh, as heavy rain may cause fast flowing or deep floodwater which forecasters say could kill.
It also indicates homes and businesses are likely to be flooded and there is a risk of power cuts and that some communities could be cut off.
The southeast of Scotland could see up to 10cm of rain.
Weather warnings are in place for parts of Scotland, North Wales, and the North West and North East in England.
The Environment Agency has issued 49 flood alerts for England, advising flooding is possible, and 10 flood warnings, which mean flooding is expected and immediate action is needed.
This week has seen showers and thunderstorms in southern and eastern parts of England, with a persistent band of rain edging north and west as the week has continued.
The Met Office tweeted: “Amber and yellow warnings are in force for Thursday morning, so conditions on the roads will be treacherous for some with surface water flooding and intense rainfall.”
North Wales Police tweeted: “Assess the need for your journey, drive to the conditions and your driving ability. Please DO NOT ignore any road closure signs. Think safety.”
Transport for Wales tweeted: “Continued heavy rain during today means that travel to and from your desired destination cannot be guaranteed.”
On Wednesday, heavy rain and flooding affected rail services in the North West and Wales.
Additionally, the lines between Shrewsbury and Chester and Crewe and Chester were closed, while a burst water main flooded the railway between Petts Wood and Orpington in London.
In Aberdeen, Scotland, an outdoor Rod Stewart concert was cancelled “due to adverse weather conditions”.
Flooding was also reported in counties including as Nottinghamshire and Warwickshire.
Met Office meteorologist Luke Miall warned that the wet weather would continue to blight parts of the country on Thursday.
He said: “As this system pushes up from the South East through the course of the night, it will re-intensify and continue through much of Thursday.”
Mr Miall said parts of southeast Scotland could see up to 10cm of rain, with an amber alert in place warning of heavy downpours.
The wettest June for the UK was in 2012 when an average of 14.9cm of rain fell but Mr Miall said this month’s rainfall was “still a long way off” breaking that record.
No Met Office weather warnings are in place at for Friday and the weekend.