Spain: Adverse weather forecast for northern regions through at least Dec. 7 /update 1

Heavy rainfall and snow forecast across northern Spain through at least Dec. 7. Possible disruptions to transport, business, and utilities.

Event

Heavy rainfall, thunderstorms, and snowstorms are forecast across parts of northern Spain through at least Dec. 7. The affected area includes Asturias, Cantabria, northern Basque Country, northern Navarre, northern Aragon, Andorra, northwestern Catalonia, southern La Rioja, and northern, eastern, and southeastern parts of Castile and Leon regions.

As of Dec. 1, the Spanish State Meteorological Agency has issued orange-level warnings (the second-highest on a four-tier scale) for snowstorms in elevated areas of northern Castile and Leon, southern Asturias, and far western Cantabria regions. Yellow-level warnings for snowstorms have been issued across the rest of the affected area, except for coastal regions of Asturias, Cantabria, and Basque regions, where yellow-level rainfall warnings have been issued. Further rain, thunderstorms, and snowfall are forecast across northern regions through at least Dec. 7, and officials could update and possibly extend the coverage of weather alerts over the coming days.

Hazardous Conditions
Where precipitation falls as rain, flash and areal flooding could occur. 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 the higher elevations over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in mountainous areas. Rain-induced landslides cannot be discounted in areas of elevated terrain; there is also the possibility of avalanches in mountainous areas where the snowpack has become unstable due to heavy snowfall. Power outages could occur in areas affected by snowfall.

Transport
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. Mountain passes and tunnels could be closed as a precautionary measure during periods of intense snowfall. Flooding and 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.

Advice

Monitor local media for weather-related updates and advisories. Confirm all transport reservations and business arrangements before traveling in the affected area. Seek updated information on road conditions before driving or routing shipments through areas where severe weather is forecast; plan for possible supply chain disruptions throughout the affected areas. Stay away from elevated streams, creeks, and other watercourses that are prone to flash flooding. Do not attempt to navigate flooded roadways. Exercise caution in elevated terrain due to the threat of landslides, as well as mountainous regions where avalanches pose a threat. Charge battery-powered devices in the case of prolonged electricity outages.