Die Vorhersage bzw. Unwetterwarnung für den Tag war wohl recht konkret, legt wenigstens dieser Artikel nahe.

The state weather agency, AEMET, launched a red alert for the Valencia region on Tuesday morning, keeping it active as conditions deteriorated throughout the day.

But it took until after 8pm for the civil protection service to send an alert urging residents not to leave home.

One man told news site Eldiario.es that the alert came as he was already trapped in his car with floodwaters up to his chest. “Just after 8pm, after an hour with water up to my neck and swallowing mud, the alert went off,” he said.

Ich kann leider kein Spanisch, also kann ich das nicht so wirklich verifizieren. Vielleicht findet ja jemand präzisere originale Quellen.