A man and a woman died after they were caught beneath rubble when a tree blown over by hurricane-force winds caused a suspected gas explosion, Scotland Yard said.
Detectives found the body of the man, in his 40s, at around noon at the address in Bath Road, Hounslow, west London . He has been identified and next of kin have been informed.
The woman was found dead an hour and a half later and police are working to establish her identity.
Three houses were damaged by the blast, which is thought to have been caused by a ruptured gas main.
Emergency services also took three people to hospital, with a man receiving treatment for a cut to the face and a woman for a cut to the ear.
Both have been discharged, while a third woman remains in hospital with burn injuries to her hand.
The two deceased were among four victims killed as Britain was battered by a storm which swept across the South West, South East, Midlands and East of England.
Six fire engines attended the scene in Hounslow after receiving a call at 7.35am, London Fire Brigade said.
London Fire Commissioner Ron Dobson, said: "My thoughts are with the friends, family and loved ones of those who lost their lives in Hounslow today.
"Firefighters and investigators remain at the scene to establish what caused the gas explosion.
"It's been a busy and challenging day for our firefighters, officers, and control officers but all have performed admirably.
I would like to pay tribute to all of the emergency service workers who have been on duty in the capital today."
Station manager Matt Burrows, who was at the scene shortly after the incident, said the three houses had been completely destroyed by the blast, leaving debris scattered over an area of around 50 metres.
"The roof of one of the houses was in a tree across the road," he said.
"Highly trained search and rescue crews searched through the rubble with sniffer dogs, and sadly two people were found dead."
"We're still investigating whether the fallen tree caused the gas explosion or whether the gas explosion caused the tree to fall. It's likely firefighters will be on scene for much of the rest of the day."
Twenty five people were evacuated from surrounding properties as a precaution.
Joe Stringer, 23, a ground worker for nearby Hounslow Highways road maintenance service, explained that he and his colleagues had noticed a tree on top of a car at 7.20am but had "just giggled it off".
"We went back to our compound and then we heard an almighty explosion," Mr Stringer said.
"People thought it was a plane crash. There was a massive cloud of smoke coming towards us."
After running to the scene, Mr Stringer said he found an Irish woman standing outside her home, covered in blood and crying.
"The whole thing was quite shocking," he said.
Local MP Seema Malhotra said: "London Fire Brigade and Hounslow Council are to be commended for their swift and compassionate response at this time of crisis in the Hounslow West community.
"However questions need to be asked about how the falling of the tree led to such a devastating gas explosion and we await the report of the fire services.
"I will be working with the council to ensure that the needs of the residents who have lost their homes today will be met and every support given at this time."
Mayor of London Boris Johnson said: "I was saddened to learn of the deaths of a man and a woman in Hounslow following the storm.
"I'm sure I can speak for all Londoners when I say my thoughts are with the victims and their relatives.
"The emergency services and Transport for London have done an amazing job responding to a host of difficult incidents whilst keeping London moving wherever possible, but clearly any loss of life is a tragedy."