About 30 residents have been evacuated and part of a building has been destroyed following a suspected explosion.
London Fire Brigade said it was called to a fire after the suspected blast on High Street in Hampton Hill, south-west London, on Tuesday night.
On social media, one witness described hearing a “boom” before the blaze. No was injured.
Road closures remain in place at the scene, Richmond Council said.
Homes have been evacuated, motorists stranded and trains cancelled as flooding hit parts of England.
The Environment Agency has issued 25 flood warnings and 64 alerts across the country.
The majority are across the Midlands and North West, although warnings are also in place in Ruswarp, near Whitby, and Petts Wood in south-east London.
The Met Office has given yellow warnings for rain across Manchester, Liverpool and the North East.
The River Steeping at Thorpe St Peter near Skegness, Lincolnshire, burst its banks on Wednesday night following heavy rain.
The rising river also caused problems in Wainfleet, where residents have been evacuated.
Jean Hart, who has lived in the town for 40 years, said it was the worst flooding she had ever seen.
“To see our house underwater is absolutely horrendous,” she said.
Emergency services have said they will rescue her tortoise Mr T and cat Aurora from her home after she had to leave them behind.
The Cricket World Cup match between India and New Zealand at Trent Bridge in Nottingham has been delayed due to rain, with a pitch inspection due at 11:30 BST.
Rail services between Skegness and Boston have been suspended until Saturday due to flooding, while Merseyrail has cancelled some trains on the Chester and Ellesmere Port lines because of water on the tracks at Hooton.
The company said journeys “could be significantly longer” and has launched an amended timetable with replacement buses.
Standing water is also causing problems on many North West roads, including the M53.
Health bosses are warning people heading to Arrowe Park Hospital to avoid using junction 3 of the motorway.
Motorists including a minibus of Indian tourists became trapped at Lambley, near Nottingham, overnight and were taken in by local residents.
Resident Malcolm Bamford said: “We had two in our house and the neighbours had three, and then there was a group of about eight Indian tourists in a little tiny bus and they all wanted to use the toilet.
“At one time we had about a dozen people in my little bungalow.”
Trains are also expected to be disrupted all day between Worcestershire and Warwickshire.
National Rail Enquiries said heavy rain had flooded the tracks between Whitlocks End, near Solihull, and Stratford-upon-Avon.
Chillingham in Northumberland saw nearly 10mm of rainfall in the space of an hour on Thursday morning, the Met Office said.
The village had 73mm of rainfall over a 28-hour period – more than the 66.4mm average for the whole of June.
Elsewhere, Waddington in Lincolnshire saw nearly 40mm fall over a period of 14 hours, while over the same period Coleshill in Warwickshire had 30mm fall and 31mm was seen at Astwood Bank, Worcestershire.