A visual guide to understanding the deadly floods in Spain

The floods in the Spanish province of Valencia have killed at least 155 people, and dozens more are still missing. The rising river levels in the province caused river banks to overflow, catching residents off guard, as alerts were only issued eight hours after the ravines had started to flood.

Most of the fatalities occurred near the Rambla del Poyo, a watercourse which runs through the town. This area was struck by a sudden flash flood that took residents by surprise. As some survivors described it: “It came like a wave, as if it were a tsunami.” The video below vividly illustrates this, showing the initial moments of the flood unfolding in front of the Paiporta town center.

Dozens of towns in Valencia were flooded after Tuesday’s rains brought over 400 millimeters to municipalities like Buñol, Chera, Cheste, Turís, and Chiva.

In Chiva, for example, the rainfall nearly matched the area’s typical annual total, according to Rubén del Campo, the spokesperson for Spain’s meteorological agency Aemet. “A relatively strong storm, a powerful downpour like those we see in spring or summer, can bring 40 mm or 50 mm. This storm was almost 10 times that amount,” he told EL PAÍS.

As shown in the following graph, the Júcar Hydrographic Confederation rain gauge registered 160 mm, illustrating the severity of the torrential downpour: by Tuesday morning, the highest reading was 34 millimeters. By 1:00 p.m., a rain gauge station in Sierra del Ave, in an inland area of the province, recorded over 100 mm, the first to do so. By the end of the day, about 20 other stations had surpassed this level. The storm’s peak intensity came in the afternoon; between 6:00 and 7:00 p.m., the Chiva rain gauge recorded over 120 mm. The graph below shows the intensity of this rainfall event across Valencia province.

Rainwater rapidly flowed through gullies and rivers, causing them to overflow and flood surrounding municipalities. Notably, the Rambla del Poyo recorded so much rain that one of the bridges that crosses it collapsed.

Emergency services were overwhelmed by the scale of the devastation, and people began posting calls for help on social media.

Accounts from individuals caught off guard by the downpours are emerging from the hardest-hit areas: Utiel-Requena, Hoya de Buñol, l’Horta de Valencia, and La Ribera. The extent of the damage in these areas only began to come to light on Wednesday, following a night of chaos. Dozens of people were forced to spend the night in Valencia on top of trucks or cars, on the roofs of shops or gas stations, or trapped in their vehicles on congested roads until they could be rescued.

The rains have caused power outages affecting 140,000 people, and more than 50 roads remain closed. Most trains are not operating.

The extreme weather is the result of the gota fría — literally “cold drop,” a term used in Spain to describe a sudden drop in temperatures along the east coast caused by the arrival of very cold polar air. “In meteorological jargon, this episode is known as a convective train, a situation in which very intense storms are continuously regenerated in the same area, which leaves exorbitant amounts of precipitation in that area,” said Del Campo.

With reporting by Montse Hidalgo, Jose A. Álvarez Iguacel, Yolanda Clemente, Jacob Vicente, Kiko Llaneras and Borja Andrino.

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