LONDON — The rain seemed typical enough in a nation known for its soggy weather. But a relentless storm on Monday turned into flash flooding in southern England, bringing part of the capital to a standstill.
The downpour left surging water spilling into the streets of London, flowing through Underground stations, disrupting public transportation and forcing some residents to evacuate their homes. The authorities issued flood warnings for several neighborhoods and the London Fire Brigade said it received more than 1,000 calls related to flooding in the capital’s west on Monday, which trapped people in cars and damaged houses and commercial buildings.
Footage of the storm’s aftermath showed cars submerged over their wheels and people huddled under awnings on Portobello Road. Pubs offered food and hot drinks to those taking shelter.
Much of the flooding had subsided by Tuesday, after a month’s worth of average rain in a single day, but effects remained. About 120 residents were put in emergency housing overnight, local authorities for the borough of Kensington and Chelsea said, adding that they had dispatched drainage teams, plumbers and electricians to help repair public housing units in the area.
A Transport for London spokesman said in a statement that the significant flooding in different areas across the capital had an impact on services across the transport network, adding that it was working to minimize this.
Outside the capital, the downpour also spread across the south of England, flooding rail lines in the city of Southhampton.
Though individual weather incidents are difficult to link directly to climate change, policy analysts have said that climate change has increased the intensity of rainfall in London. The capital is particularly vulnerable to flooding, given much of the city is built on the River Thames floodplain. A movable flood barrier across the river, more than 1,700 feet wide, has been in place since 1982.
Analysts said the flooding was a sign that the city needed to hasten adaptations to the effects of climate change, particularly given that a heat wave is predicted in England later this month.
“We haven’t seen something on that scale yesterday for a while,” said Bob Ward, deputy chair of London Climate Change Partnership, which specializes in adaptation and resilience to extreme weather, adding the city was aware that surface flooding was a growing risk.
The city is building a new “Super Sewer,” a 15-mile tunnel under the Thames to carry away sewage and waste water and prevent flooding. But its drainage system needs to be upgraded to handle bigger volumes of rainfall, with parts dating to the Victorian era, Mr. Ward said.
“It simply wasn’t built with climate change in mind,” he added.
According to a 2019 report, about 37,000 homes are at high or medium risk of tidal or river flooding in London, and 250,000 businesses and homes could be at risk of losing access to electricity, gas and other services for up to two weeks.
And with meteorologists predicting a heat wave later this month, Mr. Ward said buildings prone to trapping heat also needed to be upgraded with better ventilation to save lives this year, pointing to 2,500 excess deaths that happened during heat waves last year.
“It’s hard to know what a normal summer is anymore,” he said.