Tide plus wind
The tide prediction gives the water level to be expected from astronomy under average weather conditions. According to the BSH, the actual water level can differ considerably depending on the weather, for example with onshore or offshore wind.
When strong onshore wind pushes the water against the coast, high tide turns out higher than calculated. When it is very much higher, it is called a storm surge.
The three classes on the North Sea
The BSH divides storm surges on the German North Sea coast, in Emden, Bremen and Hamburg, into three classes, measured above the mean high water (MHW) of the gauge: storm surge at 1.5 to 2.5 metres, severe storm surge at 2.5 to 3.5 metres and very severe storm surge at more than 3.5 metres above MHW.
The Baltic Sea has its own, lower thresholds in four classes, so the values cannot be transferred between the two seas.
Using forecasts and warnings
In addition to the tide prediction, the BSH produces a water level forecast four times a day. On the tide map you can switch between the pure tide and this water level model. When an official storm surge warning is active, the display selects the model automatically and shows the warning.
On site, the notices and closures of the authorities and municipalities apply. Mudflat walks and swimming are off limits during storm surges. The German Weather Service (DWD) also warns of gale and hurricane-force gusts; active warnings for your place are shown on the tide map as well.
On the North Sea a storm surge starts at 1.5 metres above mean high water. In a storm, follow the BSH water level forecast, warnings and closures on site.
See the tide for your placeFrequently asked questions
When is it a storm surge?
On the German North Sea coast from 1.5 metres above the mean high water of the gauge. From 2.5 metres the BSH speaks of a severe, from 3.5 metres of a very severe storm surge.
When do storm surges happen on the North Sea?
Mainly in the storm season in autumn and winter. The BSH event reports also show storm surges in summer, for example in August 2023 and August 2024.
Where can I find the current situation?
The BSH publishes the official water level forecast and warnings at wasserstand.bsh.de. Weather warnings come from the German Weather Service (DWD).