Portugal is preparing for a significant shift in weather patterns as multiple rain fronts are set to arrive this Friday, November 6, followed by a deep Atlantic Storm that could be named Bruna. According to meteorologist Filomena Martins on the program "Quente e Frio," various weather models agree on the approach of a low-pressure system in the Atlantic, which is being fed by a substantial atmospheric river. This combination is expected to generate intense rainfall and strong winds throughout the coming week.
The precipitation will not be limited to a single front; instead, several fronts are projected to cross the country from Friday through the following week. The most critical period for the potential storm Bruna is anticipated between Sunday night and Tuesday, November 8 to 10. If the depression deepens near the coast and meets specific impact criteria regarding wind and rain, the Portuguese Institute of Sea and Atmosphere (IPMA) will assign it the name Bruna, which is the second name on the official list following Adam.
Simulations suggest that certain regions could accumulate up to 100 millimeters of precipitation during this period, although these figures remain scenarios requiring confirmation. The atmospheric river acts as a corridor transporting massive amounts of water vapor from subtropical origins toward the Iberian Peninsula. When this moisture interacts with successive fronts or is forced upward by mountains, it can trigger very intense precipitation events across the entire country.
Before the rain begins, the country will experience two nights of cold temperatures. Minimums are forecast to drop significantly in inland areas, with Bragança expected to reach 1°C on Wednesday and 0°C on Thursday. Guarda is also predicted to hit zero degrees, while Braga could fall from 5°C to 2°C. The Serra da Estrela region faces the most severe conditions, with temperatures potentially reaching -4°C and a wind chill of -7°C, creating favorable conditions for frost formation in sheltered interior zones.
Once the rain starts on Friday, minimum temperatures are expected to rise in many regions due to the influx of more humid maritime air and increased cloud cover, which reduces nocturnal cooling. This weather pattern also highlights a phenomenon where vehicles may develop frost or ice even when air thermometers register positive temperatures above 0°C. This occurs because surfaces like car roofs and windows lose heat through infrared radiation on clear nights, dropping below freezing while the air measured two meters above ground remains warmer.
Sources: Observador.