Much of Malaga province has seen its weather alert for Wednesday upgraded from yellow to orange.
According to state weather agency Aemet, up to 30mm of rainfall could fall on multiple areas, including the Costa del Sol, Guadalhorce Valley and Ronda.
It means all three are now under an orange alert between 6pm and 11.59pm.
Meanwhile, the rest of the province, including Antequera and Velez-Malaga, is under a yellow warning over the same period.
Aemet said in its report that it cannot rule out the formation of both tornadoes and waterspouts in Malaga.
The service has forecast extreme rainfall and strong winds in Huelva, Sevilla, Cadiz, Malaga and Cordoba, all of which are under alert today.
The alerts come just days after a serious storm left large swathes of western Andalucia underwater – while a suspected tornado in Gibraleon, Huelva, killed one resident.
On Wednesday, the entire provinces of Sevilla, Cadiz and Huelva are also under an orange alert, while Cordoba is a yellow warning.
All five regions cannot rule out the formation of tornadoes, Aemet said in its report.
Those under an orange warning face winds of up to 70km/hr and 30mm of rainfall per hour.
Read more Andalucia news at the Spanish Eye.
