Baltic Sea floods: Warnings and current water levels at a glance!

Baltic Sea floods: Warnings and current water levels at a glance!

Today, August 30, 2025, people in Mecklenburg-Western Pomerania can look at the water levels of the Baltic Sea. These are of great importance for residents and tourists. The current water levels are examined in detail in an analysis of measuring stations in cities such as Wismar, Warnemünde, Althagen, Barth, Stralsund, Sassnitz and Greifswald. The terms “mean low water” (MNW) and “mean high water” (MHW) are particularly relevant here. The MNW for Warnemünde in the period from November 2010 to October 2020 is on average 407 cm, while the MHW is given as 617 cm. Historically, the highest flood level in Warnemünde was measured at 770 cm on November 13, 1872, while the lowest level was 332 cm on a cold autumn day in 1967. This shows the enormous variability of the water levels in this coastal area and how much nature thrives here.

What's next with the storm surges? According to the Ostsee-Zeitung, storm surges are divided into different classes: A storm surge is between 1.00 and 1.25 m above mean water level, while a very severe storm surge reaches over 2.00 m. This distinction helps to identify possible dangers for coastal residents at an early stage. In the event of flooding, communities are warned by flood control centers, the police or fire brigade. State-of-the-art warning channels, ranging from radio to social media, ensure that everyone can be informed in a timely manner.

Recent experiences with storm surges

Events at sea are not always friendly. In October last year there was a severe storm surge that caused damage amounting to 56 million euros. The city of Sassnitz was particularly affected, reporting a financial need of around 42 million euros to restore its infrastructure. In addition, there are 6 million euros required for artificial nourishment to compensate for the loss of sand on beaches and dunes.

But what drives the storm surges? According to the Federal Environment Agency, strong winds that push water masses against the coast are the main cause of these natural forces. In addition, there are global climate changes that are causing sea levels to rise and thus increasing the initial levels for possible storm surges. Winds from the west pose a particular danger on the North Sea coast of Schleswig-Holstein, while winds from the north are critical in Lower Saxony.

A look into the past and the future

The history of storm surges on the German coast goes back up to 2,000 years. Some of the most devastating events have occurred in the last 100 years, including the catastrophic storm surge of 1962 in Hamburg. Other significant floods occurred in 1976, 1981, 1999 and 2013. Most recently, in 2022, several severe storm surges were recorded on the North Sea coast. The water levels on the Baltic Sea, which are considered a storm surge if they are one meter above the average water level, have also risen in recent years, as measurements in Wismar show. Values ​​of 1.83 m were achieved in 2017 and even 1.91 m in 2019.

Only three storm surges have been recorded so far in the current 2024/2025 season, but there are indications that the weather situation could bring more intense conditions again next year. The changes in storm surge intensities can be clearly seen in the annual highest flood at Baltic Sea gauges and the highest tidal flood at North Sea gauges, which have a periodicity of around 50 to 70 years.

The frequency of storm surges may not necessarily increase, but the intensity could increase under the same weather conditions. Every storm surge represents a particular challenge for coastal residents and requires constant attention from authorities and the public.