Swathes of the country face flooding after torrential downpours struck southern England.
The Environment Agency has issued 51 flood warnings after heavy rain fell on Wednesday night and continued into the early hours of Thursday.
Emergency services received hundreds of calls regarding food-related incidents after a low-pressure system named Storm Aurore moved in from France.
Warnings have been put in place along the east and south coasts of England, with residents told to "act now" and move vehicles to a higher land level, put important items upstairs and erect property protection barriers.
Operators of the Thames Barrier announced they will close their flood gates for the 200th time to avoid “widespread damage and disruption across the capital.”
The Environment Agency said the move will protect the capital "from a high tide as a result of low pressure and northerly winds coinciding with spring tides".
The barrier will remain closed until 5pm today.
A spokesman for the Environment Agency said: "While the barrier will help to protect London from tidal flooding, there are also risks from coastal flooding along the east coast on Thursday and Friday.
"Heavy rain also means that there is a separate but concurrent risk of river flooding across the south of England."
The wet weather came on Wednesday night as a low-pressure system named Storm Aurore moved in from France, bringing up to 50mm of rain and 45mph gusts.
The #ThamesBarrier will close for the 200th time today to protect #London from #flooding!
That’s 200 times we’ve avoided widespread damage & disruption across the capital
Meanwhile @TE2100Plan we’re planning for the future to ensure we can protect London from rising sea levels pic.twitter.com/7TyQ0LNUmi
— Thames Estuary 2100 (@TE2100Plan) October 21, 2021
Essex Fire Service said it had received more than 120 calls up until 2.30am on Thursday regarding flood-related incidents.
A Met Office yellow weather warning was in place until 3am on Thursday.
Its forecast said Thursday would be "a much colder day with a band of rain across central and south-western parts clearing south-east in the morning".
It said showers would then mainly affect western and northern areas, and they could turn wintry over some northern hills.
One reading from Wandsworth in southwest London suggested three inches of rain had fallen in one 24-hour period yesterday.
Thursday night will see "showers for northern and western areas, whilst eastern and southern areas will have fewer showers and more in the way of clear spells, remaining breezy", the Met Office added.
Lorry drivers are also facing long delays to enter the port of Dover after Storm Aurore struck parts of the south and south-east of England.
Six miles of queues can be seen stretching back to Capel-le-Ferne in Folkestone, Kent.
Meanwhile, Police and Highways England were called to the M26 in Kent just after 11pm on Wednesday after a number of vehicles became stranded in deep flood water.
Police managed to clear the drains and helped to tow away those who had been trapped.
Footage posted on social media shows a bus in Purley, south London ploughing through floodwater with water rising near the ankles of its passengers.
Transport for London was forced to close Maida Vale tube station last night due to “severe flooding”.
Operators of the Thames Barrier announced they will close their flood gates for the 200th time today to avoid “widespread damage and disruption across the capital.”