Tennis ball-sized hail pummels northern Germany, causing millions in damage and closing Hannover airport

Unwetter strikes

A severe thunderstorm front swept across northern Germany on Monday evening, bringing heavy rain, destructive hail and wind gusts of around 90 km/h. The system moved through parts of Niedersachsen and Mecklenburg-Vorpommern between 21:00 and the early hours of Tuesday, generating a wave of emergency calls. In the Hannover region alone, 2,300 calls temporarily overloaded the lines.

I first heard a noise and thought a tree was being cut down. Then I looked out the window. And yes, tennis-ball-sized hailstones coming down.

Heidenau: "Inferno, Inferno einfach"

The village of Heidenau, south of Hamburg, bore the brunt of the hail. Residents described the storm as unprecedented; hailstones shattered car windows, dented bodywork and punched through roof tiles. Firefighters struggled to respond because the risk of injury from the falling ice was too great.

Leaving the front doors was almost impossible for the emergency personnel because the risk of injury was so great. Entire streets in Heidenau were damaged by the hail. That means roofs were pierced and will need to be repaired in the coming days.

Early damage estimates for Heidenau alone run into the millions of euros. One resident told reporters that nothing was left intact, rain was pouring through the roof into apartments, and her housemate's brand-new car was a write-off.

Deployment marathon

Fire brigades were stretched to their limits. In the Hannover region, crews responded to around 1,000 weather-related incidents. Basements, lift shafts, underground garages and streets were flooded. In Sarstedt, a woman trapped in her cellar by rising water was rescued and taken to hospital. Across Niedersachsen, firefighters were dispatched roughly 600 times, and by Tuesday morning police in Hannover had collected about 50 license plates lost in the floods.

In Mecklenburg-Vorpommern's Ludwigslust-Parchim district, hailstones piled up so heavily that front-end loaders had to clear the roads. The local control centre recorded 168 weather-related emergency calls within a single hour. In Celle, 21 call-outs dealt with flooded basements and an underground garage where water stood 30 centimetres deep.

Hannover airport and other disruptions

Hannover-Langenhagen airport suspended operations for about one hour on Monday evening for safety reasons. In Wittenburg, a printing house was damaged, delaying or cancelling several regional newspapers. Numerous false alarms were triggered at buildings across Hannover, likely set off by the storm.

What happens next

The German Weather Service (DWD) warns that severe thunderstorms are expected again on Tuesday, focused on Saxony, Saxony-Anhalt and Thuringia. In Niedersachsen, localised heavy rain may return. The west and south-west of the country are under a heat stress warning. Clean-up in Heidenau and other affected towns is expected to take days.