Northern Europe: Adverse weather forecast across Denmark, northern Germany, and northwestern Poland through at least early June 27

Event

Thunderstorms are forecast across parts of northern Europe through at least early June 27. The affected area includes much of Denmark and parts of northern Germany and northwestern Poland. Heavy rainfall, strong winds, lightning, and possible hail may accompany storms. Heavy downpours could trigger flooding in low-lying areas and landslides on unstable slopes. Strong winds could cause damage to property and power outages.

As of June 26, the meteorological agencies for the respective countries have issued the following warnings across the affected region:

• Orange thunderstorm warnings (the middle level on a three-tier scale): Across eastern and northern parts of Jutland, Zealand, and surrounding islands in Denmark; parts of far northwestern Schleswig-Holstein State in Germany; and northwestern and western Lubuskie and central, northern, and western West Pomerania provinces.

• Yellow thunderstorm warnings: Bornholm, Funen, and surrounding islands in Denmark; and parts of western Lower Saxony and northern Schleswig-Holstein states.

• Yellow strong wind warnings: Across Schleswig-Holstein and parts of northern Lower Saxony and northern and western Mecklenburg-Vorprommern states in Germany.

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

Hazardous Conditions
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 rainfall has saturated the soil.

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

Transport
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. Severe weather could also trigger flight delays and cancellations at airports in the region. 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.

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.

Advice

Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

MeteoAlarm
Danish Meteorological Institute (DMI)
German Meteorological Service (DWD)
Poland Institute of Meteorology and Water Management (IMGW)