Spain has issued dozens of weather alerts for severe rainfall, including the feared red-level warning.
The most serious alert is in place for Valencia and parts of Catalonia, including Tarragona, where Aemet has forecast up to 180mm per square metre in as little as four hours.
The red alert was issued for Tarragona and Castellon north on Sunday night, and across the entire Valencia coast on Monday.
While Andalucía and the Costa del Sol are not under red alert, they remain on yellow warnings, with forecasters predicting intense downpours, strong winds and dangerous storm surges.

‘Extreme risk to life’ in east Spain
Spain’s national weather agency said the red alert meant an ‘extreme risk to life’, with emergency services on standby in Valencia and Catalonia.
Residents are being urged to avoid unnecessary travel and to stay indoors wherever possible.
Yellow warnings stretch across Andalucia, Castilla-La Mancha, Murcia and much of the eastern coast, leaving much of the peninsula on storm watch.
Costa del Sol on guard
On the Costa del Sol, the yellow warnings are in place from midnight until 2.49pm on Monday.
Aemet predicts that up to 40mm of rain could fall in the space of 12 hours.

The rainy weather is being caused by the effects of Hurricane Gabrielle, which will have become a storm by the time it passes by Spain.
However, it will still be felt, with heavy rain forecast in western Andalucia.
Parts of Sevilla province and Huelva are were placed on yellow alert for heavy rain on Sunday.
Read more Andalucia news at the Spanish Eye.