NOTICE Nº/7/DCS/2025 DATE 18-03-2025 TIME 15:00

NOTICE TO THE POPULATION PRECIPITATION, WIND AND ROUGH SEAS

PREVENTIVE MEASURES NATIONAL EMERGENCY AND CIVIL PROTECTION AUTHORITY

1.SITUATION

The Portuguese Institute of the Sea and Atmosphere (IPMA) predicts, for the coming days, a worsening of the meteorological situation in mainland Portugal due to depression MARTINHO with precipitation, sometimes heavy and persistent, wind and rough seas, highlighting: – Precipitation, sometimes heavy and persistent, which may be hail and accompanied by thunderstorms, especially in the central and southern coastal regions;

• Strong winds, with gusts of up to 75km/h in most of the territory, reaching 120km/h in high areas. Conditions favourable to the occurrence of extreme wind phenomena, especially in the Central and South regions;
• Strong sea agitation south of Cabo Mondego;
• Snowfall at the highest points of Serra da Estrela.

Meteorological information at www.ipma.pt

Hydrological Information

According to information from the Portuguese Environment Agency (APA), the following is highlighted for the next 48 hours: – Tagus Basin – in urban basins there may be an increase in flow rates, possibility of flooding;

• Urban basins and rivers in the West – according to hourly precipitation values obtained from weather forecasts, in urban basins (Cascais, Oeiras, Lisbon, Loures, Odivelas, Setúbal) flows with a return period of between 5 and 10 years may be reached;
• Sado Basin – possibility of increasing the tributary flows to the dams. Flows in the Sado River may increase;
• Guadiana Basins – Inflows to Monte Novo may increase. There may be an increase in flows in the Guadiana River;
• Algarve Ribeiras Basin (Sotavento) – There may be an increase in flow rates.

Hydrological information at https://apambiente.pt.

2.EXPECTED EFFECTS

This meteorological situation is expected to be more serious from the afternoon of March 19th to the morning of March 20th, with the following expected:

• The occurrence of flooding in urban areas, caused by the accumulation of rainwater due to obstruction of drainage systems or coastal overtopping;
• The occurrence of floods, increased by the overflow of the beds of some watercourses, rivers and streams;
• The instability of slopes, leading to mass movements (landslides, slides and others) caused by water infiltration, a phenomenon that can be exacerbated by the removal of vegetation cover following rural fires, or by artificial soil development;
• Slippery road surface due to the possible formation of water;
• Possible accidents on the shore, due to strong sea waves;
• Drifting of loose objects onto roads, or the detachment of mobile or poorly fixed structures, due to episodes of strong winds, which can cause accidents with vehicles in circulation or pedestrians on public roads;
• Thermal discomfort in the population due to increased wind intensity.

3.PREVENTIVE MEASURES

The National Emergency and Civil Protection Authority (ANEPC) reminds that the eventual impact of these effects can be minimized, mainly through the adoption of appropriate behaviours, so that, and particularly in historically more vulnerable areas, it is recommended to adopt the main preventive measures for these situations, namely:

• Ensure the unblocking of rainwater drainage systems and removal of inert materials and other objects that could be dragged or create obstacles to the free flow of water;
• Ensure adequate fixing of loose structures, in particular scaffolding, placards and other suspended structures;
• Take special care when walking and staying near wooded areas, being aware of the possibility of branches and trees falling due to stronger winds;
• Take special care when moving along the coast and riverside areas that are historically more vulnerable to coastal flooding, avoiding moving around and staying in these areas.
• Do not engage in activities related to the sea, namely sport fishing, water sports and walks along the seafront, and avoid parking vehicles too close to the seafront;
• Adopt defensive driving, reducing speed and paying special attention to the possible formation of sheets of water on the highways;
• Do not cross flooded areas, in order to prevent people or vehicles from being dragged into holes in the pavement or open drains;
• Remove animals, agricultural and industrial equipment, vehicles and/or other goods from areas bordering water courses, which are normally subject to flooding, to safe locations;
• Pay attention to weather information and instructions from Civil Protection and Security Forces.

ANEPC | Communication and Awareness Division