Spain, Andorra: Adverse weather forecast across northern Spain and Andorra through at least Dec. 6 /update 2

Heavy rainfall and snow forecast across northern Spain and Andorra through at least Dec. 6. Transport and utility disruptions possible.

Event

Heavy rainfall and snowstorms are forecast across parts of northern Spain through at least Dec. 6. Up to 20 cm (8 inches) of snowfall is forecast in some elevated areas on Dec. 5 and heavy rain is expected along parts of the north coast. The Spanish State Meteorological Agency has issued the following warnings across the affected area:

Orange snowstorm warnings (the second-highest on a four-tier scale): northern Aragon Region and Andorra.
Yellow snowstorm warnings: northern and eastern Castile and Leon, southern La Rioja, northeastern Navarre, and northwestern Catalonia regions.
Yellow rainfall warnings: coastal areas of eastern Asturias, Cantabria, and Basque County regions.

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.