National weather agency AEMET kept coastal areas of Valencia province under red alert for the whole of Monday because of the risk of torrential rain.

It said as much as 180 millimetres of precipitation could fall in these eastern areas in the space of 12 hours.

Images on social media showed roaring torrents of water gushing through the town of Cullera, south of the regional capital Valencia.

"We have experienced an episode of historic rains," Cullera's mayor Jordi Mayor said in a statement on social media, pleading with locals to stay at home.

An event at the University of Valencia due to be attended by King Felipe VI on Tuesday had been cancelled due to the adverse weather forecast, the royal palace announced.

Monday's La Liga football match between Valencia and Real Oviedo was also postponed due to the weather alert, the Spanish Football Federation said. It is now set for Tuesday, weather permitting.

More than half a million students across the Valencia region had no lessons on Monday because 243 local councils in the region closed their schools as a precaution, regional education authorities said.

Valencia city also closed all public spaces, including libraries, parks, markets and cemeteries.

Earlier, overnight downpours had caused localised flooding and made a ravine overflow in Aldaia, one of the towns hardest hit by the October 2024 disaster that killed more than 230 people. No injuries were reported.

"There is a bit of panic because of what happened. People are very scared," 64-year-old pensioner Jose Luis Ruiz told AFP in Aldaia.

"Everyone moved their cars away from the area. We set up barriers outside our doors. We had a bit of a sleepless night."

Last year's floods sparked public fury over warning systems and the emergency response. Residents continue to protest, accusing officials of failing to provide timely alerts.

Because a warmer atmosphere holds more water, climate change increases the risk and intensity of intense rainfall and flooding.