Portugal: Adverse weather forecast across northern and north-central regions Nov. 8

Heavy rainfall is forecast across northern and north-central coastal areas and adjacent inland areas of mainland Portugal Nov. 8. Rainfall amounts of 2-4 cm (0.8-1.6 inches) per hour are possible in parts of the affected areas. The heavy downpours could trigger flooding in low-lying areas and landslides on unstable slopes.

The Portuguese Institute of Meteorology (IPMA) has issued the following weather warnings across the affected area:

• Orange heavy rainfall warnings (the middle level on a three-tier scale): Aveiro, Braga, Porto, and Viana do Castelo districts

• Yellow heavy rainfall warnings: Coimbra, Vila Real, and Viseu districts

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

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Floodwaters and debris flows may render some bridges or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Severe weather could also trigger flight delays and cancellations at regional airports.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.