Barcelona and surrounding areas of Catalonia have been hit by another round of torrential rain and flash flooding, bringing renewed disruption only hours after severe storms left two people dead and another person missing.

Authorities issued another red weather alert on Monday, October 5, as intense thunderstorms swept across the region during the morning rush hour, flooding roads and trapping some motorists in their vehicles.

The latest downpours come after a destructive weekend in which flooding affected communities across the Barcelona metropolitan area and other parts of Catalonia.

Second red alert in just 48 hours

Parts of Catalonia were placed under their second red alert in less than 48 hours as another powerful storm moved across northeastern Spain.

Heavy rainfall quickly overwhelmed drainage systems in some locations, turning roads into streams and causing significant problems for commuters.

Barcelona and surrounding coastal and inland areas experienced some of the most intense rainfall during the morning, adding to already saturated ground from the weekend storms.

Authorities urged residents to avoid unnecessary travel and warned people not to attempt to cross flooded roads.

Two people killed in previous flooding

The latest severe weather follows deadly flooding across Catalonia over the weekend.

A man was killed in Tordera after a wall collapsed, while another person died in Montornès del Vallès. Authorities were also searching for a person reported missing in Pineda de Mar.

Floodwaters entered homes and businesses and submerged vehicles across several communities.

Images from Sant Adrià de Besòs, on the outskirts of Barcelona, showed recreational areas near the Besòs River covered by floodwater following the intense rainfall.

Transport severely disrupted

The storms have also caused major travel disruption.

During the earlier phase of the severe weather, local rail services were interrupted, flights at Barcelona airport were affected and several major public events were cancelled.

Flooded roads created additional problems for drivers, while authorities repeatedly urged people to stay indoors during the most dangerous periods.

The return of torrential rain on Monday increased concern that already saturated areas could flood again very quickly.

Why repeated rainfall increases the danger

Repeated thunderstorms can be particularly dangerous when the ground is already saturated.

Once soil can no longer absorb additional water, rainfall runs rapidly into rivers, drainage systems and low-lying streets.

This can lead to flash flooding even when individual storms last only a relatively short time.

Urban areas such as Barcelona are especially vulnerable because large amounts of concrete and asphalt reduce the amount of water that can naturally soak into the ground.

Mediterranean storm remains a concern

Meteorologists have been closely monitoring the unstable weather pattern over the western Mediterranean.

Warm and moisture-rich Mediterranean air can provide large amounts of energy for thunderstorms, particularly when it interacts with cooler air higher in the atmosphere.

Under the right conditions, thunderstorms can repeatedly develop over the same locations, producing extremely high rainfall totals in a matter of hours.

Officials warned that the risk was not limited to Barcelona itself, with other parts of Catalonia also vulnerable to intense rainfall.

Residents urged to avoid flooded roads

One of the most important safety messages from authorities is to never attempt to drive through floodwater.

Even relatively shallow moving water can sweep vehicles away, while road surfaces beneath floodwater may have been damaged or completely washed out.

People living close to rivers, streams and other flood-prone areas are being advised to monitor official warnings and be prepared to move to safer locations if conditions deteriorate.

More rain could bring further flooding

The key concern now is how quickly the storm system moves away from Catalonia.

With soils already saturated and rivers running high, additional heavy rainfall could trigger further flash floods with little warning.

Emergency services remain on alert as northeastern Spain deals with another episode of severe autumn weather.