Germany: Adverse weather forecast across much of the country through at least Dec. 23

Severe weather is forecast across much of Germany through at least Dec. 23. A storm system is expected to move over the North Sea from Dec. 21 and will bring strong winds especially over northern and mountainous regions. Persistent rainfall is expected in central mountainous regions and a mix of rainfall and snowfall in southern regions. Isolated storms and showers are likely across many other parts of the country over the coming days and snowfall is possible in elevated areas. Persistent heavy downpours could trigger flooding in low-lying areas and strong winds may cause property damage and power outages. Hazardous travel conditions are likely in mountainous areas due to reduced visibility caused by blowing snow.

As of Dec. 20, the German Weather Service (DWD) has issued the following weather warnings across the country:

• Red heavy rainfall warnings (the second highest level on a four-tier scale): Parts of the Harz mountains in southeastern Lower Saxony State.

• Orange heavy rainfall warnings: Parts of northwestern and western Hesse, eastern and southern North Rhine-Westphalia, and northern Rhineland-Palatinate states.

• Orange thunderstorm warnings: Parts of eastern Brandenburg State.

• Orange snowfall warnings: Parts of southeastern Bavaria State.

• Orange strong wind warnings: Across parts of central, eastern, northern, and southern Germany.

• Yellow snowfall warnings: Parts of eastern, southeastern, and far southwestern Baden-Wurttemberg and eastern and southern Bavaria states.

• Yellow strong wind warnings: Across much of the rest of the country not under orange strong wind warnings.

• Yellow frost warnings: Parts of southern Bavaria State.

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

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 or a lack of stormwater drainage systems. Sites located downstream from large reservoirs or rivers 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. Disruptions to electricity and telecommunications services are possible where significant winds, flooding, or landslides impact utility networks.

Floodwaters and debris flows may render some bridges, rail networks, 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. 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.

Severe weather could also trigger flight delays and cancellations at regional airports. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.