Spain is reeling from its worst flooding in decades, after a year's worth of rain fell in just hours in the country's southern and eastern regions.
Valencia saw its heaviest rainfall in 28 years, catching people off guard as they headed home from work on Tuesday evening.
Spanish Red Cross staffer Arturo Valoria de Arana likened the devastation to a tsunami disaster.
"Valencia and the surrounding areas are full of water, there's mud and hundreds and hundreds of cars piled all over in the streets," Mr Valoria de Arana told ABC News Radio this morning.
At least 158 people have been killed so far by the flash flooding.
As emergency workers fight to clear debris and recover bodies, it could become Europe's worst storm-related disaster in over five decades.
How did this happen?
Spain's flash floods were caused by a destructive weather system in which cold and warm air met and produced powerful rain clouds.
The phenomenon is known locally as DANA, a Spanish acronym for high-altitude isolated depression.
It's a pattern believed to be becoming more prevalent due to climate change.
Preliminary research shows human-caused climate change made Spain's rainfall about 12 per cent heavier and doubled the likelihood of a storm as intense as this week's deluge.
This is according to a rapid but partial analysis by World Weather Attribution, a group of international scientists who study global warming's role in extreme weather.
Authorities have called this week's downpours and flooding "unprecedented".
Spain has suffered through two consecutive years of intense droughts, meaning that when the deluge happened, the soil was so hard that it couldn't absorb such a quantity of water, leading to flash flooding.
A satellite view shows residential areas and cars on fields during floods in La Torre. (Reuters: Maxar Technologies)
Freelance journalist in Valencia Melita Cameron-Wood says for many people in these communities, the devastation came out of nowhere.
"The devastation is really harrowing to see," Ms Cameron-Wood told ABC RN this morning.
"There is more rain on the horizon … there are yellow warnings currently in place for storms.
"Rainfall is expected to continue through Friday and Saturday [local time]."
People walk amid piled-up cars on a mud-covered street in the aftermath of flooding in Paiporta. (Reuters: Eva Manez)
Too little, too late to warn residents
Ms Cameron-Wood also said there had been lots of criticism over the authorities' handling of the crisis, both for their late warnings of the looming floods and the relief response.
The civil protection agency, deployed during national disasters, did not issue an alert until 8.15pm on Tuesday evening local time, by which time several places in Valencia had been flooded for hours.
But Valencia regional president Calos Mazón defended his administration's management of the crisis.
He said "all our supervisors followed the standard protocol" that was coordinated by Spain's central government.
Paiporta mayor Maribel Albalat said that at least 62 people had perished in the community of 25,000.
"Paiporta never has floods, we never have this kind of problem," Ms Albalat told Spanish national broadcaster RTVE.
How much rain actually fell?
Chiva, which is west of Valencia, recorded nearly 500 millimetres of rain in just 8 hours on Tuesday.
This is more rainfall than it had seen over the past 20 months, according to Spain's weather service.
The Valencia area averages around 77 millimetres for the entire month of October.
How does it compare to other storms Spain has seen?
While Spain is used to autumn storms that can cause flooding, nothing comes close to the devastation over the past few days.
This week's floods are the most deadly Spain has suffered in modern history.
In 1959, 144 people were killed by a flood in the Spanish town of Ribadelago.
But that disaster was caused by the failure of a dam.
The last comparable disaster was in 1996, when 87 people died near a town in the Pyrenees mountains.
A man carries a cat amid mud and debris in the aftermath of torrential rains that caused flooding in Paiporta. (Reuters: Eva Manez)
Older people in Paiporta, ground zero of the tragedy, claim that Tuesday's floods were three times as bad as those of 1957, which caused at least 81 deaths.
The region of Valencia also suffered two other major DANAs in the 1980s.
One in 1982 that killed around 30 people, and another five years later that broke rainfall records.
And what about in European history?
Meteorologists say human-driven climate change is making such extreme weather events more frequent and destructive.
In 2021, at least 185 people died in heavy flooding in Germany.
Prior to that, 209 people died in Romania in 1970 and floods in Portugal killed nearly 500 people in 1967.
With rescue teams still searching for those missing, it could become Europe's worst storm-related disaster in over five decades.
A man with a shovel stands on a mud-covered street in Paiporta. (Reuters: Eva Manez)