Torrential rain has resulted in the cancellation of one of the main celebrations marking the Queen's 90th birthday.
Downpours blighted much of south-eastern England overnight, with Kew Gardens experiencing the wettest six-hour period, clocking nearly 1in (23.6mm) of rain.
Charlwood closely followed, with 0.9in (23.4mm) falling on the Surrey village and more than 0.7in (18mm) of rain recorded in just one hour at St Catherine's Point on the Isle of Wight.
Steven Keates, from the Met Office, said across southern, central and western Britain it has been a "pretty soaking night" with some "intense downpours".
"It is atrocious out there - driving will not be that pleasant on some roads across the South this morning," he said.
The Royal Windsor Horse Show, hosting one of the main celebrations for the Queen's Birthday across the four-day event, was also impacted by the wet weather.
A water-logged public and lorry car park forced the cancellation of the first day of equine eventing.
Parts of south-east London were also brought to a standstill during the morning rush-hour.
A Transport for London (TfL) spokeswoman confirmed that the Docklands Light Railway service was suspended between Deptford Bridge and Lewisham due to flooding caused by heavy rain.
And flooding on Loampit Vale in Lewisham also spread across much of the carriageway on Wednesday morning.
Mr Keates added: "This wet weather will gradually work its way south and west over the course of this morning and into the afternoon.
"The likes of Devon, Cornwall and South Wales will see some heavy rain over the next few hours, with an improving picture across London and the South East.
"But there is scope for some heavy thundery showers around this afternoon. There will be some sunshine around and temperatures will be in the high teens giving it a humid feel."
Mr Keates said the weather in the South is in "stark contrast" to warm and sunny weather over western Scotland and northern England.
Looking ahead to the rest of the week he said there is an "improving picture" across the country and the potential for some showers in the south-west of England.
Temperatures could reach the low 20s on Thursday with these dropping by the weekend to the seasonal average of the mid to low teens.