Portugal puts 14 districts on weather alert for heavy rain, 90 km/h winds, and rough seas

Meteorological alert across mainland districts

The Portuguese Institute of the Sea and Atmosphere (IPMA) has placed 14 mainland districts under a yellow weather warning due to incoming rain, thunderstorms, and strong winds. The warning covers Aveiro, Braga, Bragança, Castelo Branco, Coimbra, Guarda, Leiria, Lisbon, Porto, Setúbal, Santarém, Viana do Castelo, Vila Real, and Viseu. Meteorologists attribute the unseasonable late-August conditions to an upper-level trough situated west of the mainland and a depression moving southeast from the Azores. IPMA meteorologist Cristina Simões explained the atmospheric setup behind the sudden shift in conditions.

We are in the presence of a depression that is west of the continental territory and approaching.

Meteorologist Paula Leitão noted that these convective atmospheric systems arrive earlier in the calendar year than customary.

They are more typical of the month of September and October, this week we will have a very unstable situation.

Rainfall intensity, wind gusts, and coastal agitation

Precipitation will begin on Sunday morning along the western coast before extending inland and to northern and central regions during the afternoon. IPMA forecasts localized hourly rainfall accumulations between 10 and 20 millimetres, hail with diameters under 2 centimetres, and wind gusts reaching between 70 and 90 kilometres per hour, particularly in highland areas and south of Coimbra. Maritime conditions on the western coast will deteriorate as wave heights rise between 2 and 2.5 metres, with some projections reaching up to 3 metres as wave directions shift from northwest to southwest. Water temperatures along the western coastline will range between 17 and 20 degrees Celsius.

Emergency preparedness and burn scar vulnerabilities

The National Emergency and Civil Protection Authority (ANEPC) issued an advisory warning residents of potential urban flooding caused by overloaded drainage networks and surface runoff. Emergency officials warned of landslides, mudslides, and slope instability, particularly across areas where forest fires destroyed roughly 63,000 hectares of vegetation since the start of 2026. The absence of plant cover increases the risk of earth and debris sliding onto roadways and contaminating drinking water supplies. ANEPC urged motorists to practice defensive driving to manage slick road surfaces and water puddles, while advising citizens to clear rain gutters, secure loose scaffolding, and avoid entering floodwaters on foot or by vehicle. Civil protection authorities also recommended moving animals, vehicles, and equipment away from routinely flooded areas and staying away from cliffs and breakwaters.

Extended weekly outlook and temperature drops

Instability will persist through the remainder of August, with rainfall expected to become heavy and continuous on Monday and Wednesday, especially in the northwestern regions of Minho and Douro Litoral. Monday afternoon will bring localized convective phenomena with wind gusts up to 60 kilometres per hour in the North and Centre before the depression tracks northeast toward Spain. While the southern region will remain more protected with lighter precipitation, a cold front approaching the western coast on Wednesday will bring additional rain to the rest of the country. Temperatures will remain below normal summer averages, with daily highs reaching 20 to 25 degrees Celsius on the coast and 28 to 30 degrees inland. Nighttime minimum temperatures between 12 and 18 degrees Celsius will decline to between 9 and 16 degrees Celsius during the second half of the week.