Portugal: Adverse weather forecast across much of the country through at least March 10

Adverse weather is forecast across much of Portugal through at least March 10. The Portuguese Institute of the Sea and Atmosphere (IPMA) has issued a special weather bulletin warning that weather fronts moving in from the Atlantic will bring heavy rainfall, thunderstorms, and strong winds across much of the country. Storms may be accompanied by lightning and hail. Rough seas are expected in coastal areas and snowfall is likely in elevated parts of central and northern Portugal. Heavy downpours may trigger flooding in low-lying areas and strong winds could cause property damage and power outages, Hazardous travel conditions are likely in elevated areas due to reduced visibility caused by blowing snow.

As of March 7, IPMA has issued the following warnings across the country:

• Orange heavy snowfall warnings (the highest level on a three-tier scale): Castelo Branco and Guarda districts March 8-10 and Braga, Barganca, Viana do Castelo, and Vila Real districts early March 8.

• Orange rough sea warnings: Across coastal areas of mainland Portugal March 7-10 and Porto Santo and northern Madeira March 7 and March 10.

• Yellow heavy snowfall warnings: Across northern and central regions March 7-10.

• Yellow heavy rainfall warnings: Aveiro, Braga, Braganca, Castelo Branco, Coimbra, Guarda, Leiria, Lisboa, Porto, Santarem, Viana do Castelo, Vila Real, and Viseu districts March 8.

• Yellow strong wind warnings: Aveiro, Braga, Braganca, Castelo Branco, Coimbra, Guarda, Leiria, Lisboa, Porto, Setubal, Viana do Castelo, Vila Real, and Viseu districts March 8.

• Yellow rough sea warnings: Southern Madeira March 7 and Porto Santo and northern Madeira early March 8 and late March 9.

Officials could update and extend the coverage of weather alerts over the coming days.

The storm system could produce rounds of heavy precipitation (including rain and snow) and strong winds across the affected area. Where precipitation falls as rain, flash and areal flooding is possible. Such flooding is possible in low-lying communities near watercourses and other large bodies of water, as well as in urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs may be subject to flash flooding after relatively short periods of intense rainfall. Precipitation could fall as snow in elevated areas over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in affected areas.

Floodwaters and related debris may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around the affected area. Flooding in urban areas could also result in significant traffic congestion. Heavy snow will likely make driving hazardous in some areas; authorities could implement temporary road closures or detours in such locations.

The disruptive weather will likely cause some delays and cancellations at airports in the region. Authorities may temporarily suspend port operations along the Atlantic coast if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic.Flooding or snow could block regional rail lines; freight and passenger train delays and cancellations are possible in areas that see heavy rainfall and potential track blockages.

Disruptions triggered by inclement weather and resultant hazards, such as flooding or strong winds, could persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. If there is severe damage to infrastructure, repair or reconstruction efforts may result in residual disruptions.