What you should know about the floods that killed over 200 people in Spain

VALENCIA, Spain (AP) — Flash floods caused by heavy rains in eastern Spain swept away almost everything in their path within minutes. With no time to react, people were trapped in vehicles, homes and businesses. Many died and thousands of livelihoods were destroyed.

Six days later, authorities recovered 217 bodies – 213 of them in the eastern Valencia region. On Monday they continued the search for an unknown number of missing people, helped by around 5,000 new soldiers who arrived over the weekend.

An angry crowd in hard-hit Paiporta hurled mud and other objects at the Spanish royal family, Prime Minister Pedro Sanchez and regional officials as the leaders made their first visit to the epicenter of flood damage on Sunday.

Further rainfall is forecast for the disaster areas and further up the Mediterranean coast, where a red alert applies in part of the Catalonia region around the city of Tarragona.

The Spanish Navy transport ship Galicia arrived at the port of Valencia on Monday with 100 marines, helicopters and trucks loaded with food and water to help with relief efforts.

Thousands of volunteers helped clear away the thick layers of mud and debris that still covered homes, streets and paths, all while grappling with shortages of drinking water and shortages of some basic goods. Some of the vehicles washed away by the water or trapped in underground garages still had bodies waiting to be identified.

Here are a few things you should know about Spain's deadliest storm in living memory:

What happened?

The storms were concentrated in the Magro and Turia river basins, creating walls of water in the Poyo riverbed that flooded the river banks and surprised people going about their daily lives on Tuesday evening and early Wednesday.

In no time, the muddy water covered roads and railways and entered homes and businesses in towns and villages on the southern outskirts of the city of Valencia. Motorists had to take shelter on car roofs while residents sought refuge on higher ground.

Spain's national weather service said the worst-hit town of Chiva received more rain in eight hours than in the previous 20 months, calling the flooding “extraordinary.” Other areas on the southern outskirts of Valencia received no rain before being wiped out by the wall of water that flooded drainage canals.

By the time authorities sent alerts to cellphones warning of the severity of the flooding and urging people to stay home, many were already out and about, working or covered in water in low-lying areas or underground parking lots, becoming death traps.

Why did these massive flash floods happen?

Scientists trying to explain what happened see two likely connections to human-caused climate change. One is that warmer air stores and then releases more rain. The other is possible changes in the jet stream — the flow of air over land that moves weather systems around the globe — that produce extreme weather.

Climate scientists and meteorologists said the immediate cause of the flooding was a truncated, lower-pressure storm system that originated from an unusually wavy and stalled jet stream. This system simply parked over the region and poured rain. This happens often enough that in Spain they call them DANAs, the Spanish acronym for the system, meteorologists said.

And then there is the unusually high temperature of the Mediterranean. In mid-August, it had the warmest surface temperature on record at 28.47 degrees Celsius (83.25 degrees Fahrenheit), said Carola Koenig of the Center for Flood Risk and Resilience at Brunel University of London.

The extreme weather event came after Spain struggled with prolonged droughts in 2022 and 2023. Experts say drought and flood cycles are increasing with climate change.

Has this happened before?

Spain's Mediterranean coast is used to autumn storms that can cause flooding, but this episode was the strongest flash flood event in recent memory.

Elderly people in Paiporta, at the epicenter of the tragedy, say Tuesday's floods were three times as bad as those in 1957, which killed at least 81 people. This episode led to the diversion of the Turia watercourse, which spared a large part of the city from these floods.

Valencia suffered two other major DANA events in the 1980s, one in 1982 with around 30 fatalities and another five years later that broke rainfall records.

The flash floods also exceeded the flood that swept away a campsite on the Gallego River in Biescas in the northeast in August 1996, killing 87 people.

What was the state's reaction?

The management of the crisis, classified by the Valencian government as level two on a scale of three, is in the hands of the regional authorities, which can ask the central government for help in mobilizing resources.

About 7,500 soldiers, trucks, heavy road equipment and Chinook helicopters, as well as nearly 10,000 additional National Police and Civil Guard police officers, were deployed to help search for bodies, clear thousands of wrecked cars and distribute emergency aid.

As many of those affected said they felt abandoned by authorities, a wave of volunteers came to help. Hundreds of people carried brooms, shovels, water and basic supplies and walked several kilometers to deliver supplies and help clean up the hardest-hit areas.

Sánchez's government will adopt a disaster declaration on Tuesday, allowing rapid access to financial aid. Mazón has announced additional economic aid.

The regional government of Valencia has come under heavy criticism for not broadcasting flood warnings on mobile phones until 8pm on Tuesday, when flooding had already begun in some places and long after the national weather agency had issued a red alert for heavy rain.