Maximum alert for rain on the Catalan coast: 40 litres in 30 minutes

Meteocat raises the alert to level 6/6 for rainfall intensity in eight counties and Civil Protection activates INUNCAT with an Es-Alert for 14 counties. The critical period will be this Tuesday, September 29, between 6:00 and 12:00 noon.

The Meteorological Service of Catalonia has raised the alert for rainfall intensity to 6 out of 6, the maximum on its scale, in the counties of Garraf, Alt Penedès, Baix Llobregat, Barcelonès, Vallès Occidental, Vallès Oriental, Maresme, and La Selva. The forecast indicates rainfall that could exceed 40 litres per square metre in 30 minutes between 6:00 and 12:00 noon, according to official warnings from Meteocat. In the vicinity of Barcelona, the expected accumulation approaches 150 litres per square metre.

Civil Protection has activated the INUNCAT plan and sent an Es-Alert message to mobile phones in 14 counties, from La Selva to Tarragonès, including Maresme, both Vallès, Barcelonès, Baix Llobregat, Garraf, Alt Penedès, Conca de Barberà, Baix Camp, Alt Camp, and Baix Penedès. The information, reported by moncloa.com, emphasises that the alert will remain active from 2:00 on Tuesday until 2:00 on Wednesday.

The message urges extreme caution in mobility and outdoor activities, and advises against approaching flood-prone areas. Civil Protection reminds that sudden increases in flow can occur in streams, brooks, and rivers.

“The water surge can arrive at any moment,” warns the agency.

For those needing to drive, the recommendation is clear: use main roads, avoid paths and secondary roads, and never cross flooded areas, even if they appear dry. Parking in riverbeds or flood-prone areas is also discouraged.

The Aemet has raised the alert to extraordinary danger in the pre-coastal and coastal areas of Camp de Tarragona, where accumulated rainfall in 12 hours could reach 180 litres per square metre. The red alert from the state agency also covers Tuesday morning.

The deputy director of Civil Protection, Inma Solé, has reminded that the rainfall will be localized and will not affect all the counties on alert equally. The Meteocat's six-level system exists precisely to gauge that uncertainty: the maximum level does not imply that it will rain the same everywhere, but that in some specific point it may fall with extreme force.

The Barcelona City Council has activated the municipal emergency plan due to drainage insufficiency in alert phase. This is a standard preventive measure during episodes of heavy rain, when a saturated drain may be enough for water to seek out unwanted paths.

The intensity will shift from Camp de Tarragona towards the pre-coastal and coastal areas during the early morning and first hours, and northwards in the afternoon, now with low danger. The next update on the alerts will arrive throughout the night.