Torrential rain has been sweeping across the country, leaving travel disruption in its wake.
What is the situation on the roads and railways in the areas affected?
Many roads in south London remain "badly flooded" according to the BBC Travel service, with Croydon and Purley badly hit, as well as Kingston in south west London.
Roads that pass under bridges, the A3 near Tibbetts Corner, Tooting Broadway, Putney High Street, Armoury Way and the Tolworth underpass were mentioned as particularly affected.
Police have warned motorists to avoid the Wandsworth area.
Berkshire, Buckinghamshire and Surrey are also badly affected, with numerous A-roads hit by floods, including the A404 and A421.
The A40 heading out of London to the west is flooded and the A3 south of Roehampton is closed, also due to floods.
The A23 in South Croydon, the M25 clockwise at Reigate and the M25 anti-clockwise at Wisley have also been hit.
A landslide is reported to be causing severe disruption on the M4 in west Berkshire between junctions 12 and 13 eastbound. In the westbound direction, flood waters are said to have reached car wheel-arch height. In east London, the A12 is partly closed in Hackney, due to flooding.
In the London area the A23 in South Croydon, the M25 clockwise at Reigate and the M25 anti-clockwise at Wisley have been hit.
Further north, the M40 in Warwickshire is closed because of flooding, as is the M50 in Worcestershire. The A443 in Worcestershire is also affected.
Severe disruption is reported, particularly between London and the West Country.
There are no trains running on the Bristol to Paddington line in either direction east of Swindon because of flooding and no trains running between Newbury and Reading in Berkshire.
A Network Rail spokeswoman said services could not restart until the flooding subsided, after which speed restrictions would probably be in place.
There is more disruption on the London to Brighton line, with all lines blocked at Thornton Heath and two out of three lines blocked at South Croydon by a landslide.
South West Trains said many of its routes had been reinstated but in some cases buses were operating replacement services. A spokesman for the company, which runs services out of London's Waterloo station, said that both the Kingston and Richmond lines had been reinstated.
But he said the Guildford to Ascot and Teddington to Shepperton routes continued to be disrupted and had been replaced by bus services.
Services in Kent are being disrupted after flooding caused a signal failure at Otford Junction. A lightning strike has further disrupted services between Sevenoaks and London Blackfriars.
Elsewhere, the Doncaster to Leeds line is blocked by flooding at Wakefield.
And in Gloucestershire, the Wickwar Tunnel is flooded, causing disruption to services between Cardiff and Bristol and Birmingham.
Hundreds of people were stranded at Gloucester railway station after trains were cancelled.
A landslide has blocked the railway line between Worcester and Birmingham. Soil has fallen across the entrance of the tunnel close to Shrub Hill station.
In Ledbury the tunnel close to the station is flooded, causing severe disruption to trains between Worcester and Hereford. There are no trains running between Oxford and Worcester.
The Circle line is suspended due to flooding.
The District Line is suspended between Turnham Green and Richmond and between High Street Kensington and Edgware Road, with severe delays on the rest of the line.
The Hammersmith and City line is now running with minor delays, after being partly suspended earlier.
Several stations are still closed because of flooding. These include Shepherd's Bush (Central Line), Colliers Wood, Paddington (Circle Line services only), Tooting Broadway and Gants Hill.
The approach to Luton Airport is flooded, causing delays to passengers trying to reach the airport. Passengers are advised to call their airline for advice.