Spain's weather service Aemet reports that around a hundred millimeters fell within a few hours near Barcelona.
The two people are said to have been swept away when the Foix river overflowed in the coastal town of Cubelles, between Barcelona and Tarragona. The rescue service says on the platform X that a search effort is underway.
The bad weather has caused chaos in various ways during the day on Saturday.
All train traffic in Catalonia was stopped as a precaution, but was resumed later in the day. A hospital in Barcelona was flooded and had to refuse patients. Roads have been blocked by masses of water and an airplane on its way to the USA had to turn back after the nose was damaged by hail.
Heavy rain has also hit, among other places, the region of Aragon.
In October last year, 225 people were killed in floods in the province of Valencia, the deadliest natural disaster that Spain has experienced in decades.
